2Ad Engine Replacement Poll

[CharlieFarlie]

Would it be better to open in another post ?? May get confusing having two subjects in one topic ?

[DjRav]

I see Nmaria said "from an early stage oil consumption was excessive".

Could be a good question too, as I believe a few were like this. My 57 plate has never used ANY oil between services, perhaps that's a sign of no issues? (bit of wishf thinking perhaps!)

So question is- have all the engine swappers always used oil from day one and it's just a case of when they escalate into a problem? In a way I hope so, as this would be a tell sign of which will need swapping.

Dave

[anchorman]

Because by the time yours had been built they were in the process of running production changes. I expected/hoped/predicted that we would se this trend. The poll should see primarily 2006/7 models but there may be a few stragglers that were registered late or the owners have wangled a new engine with boderline oil consumption.

[grangie]

Heres my twopenn'orth guys. 2008 T180 bought September 2011 by me at 33k miles from independent retailer. Full Toyota dealer service history and 12 month MOT. Car has met my needs brilliantly. No oil used. Water pump replaced a 40K (April 2012) service - dealer phoned me to tell me that replacement was needed, but they had contacted Toyota who agreed to warranty repair - outstanding. Car now on 44K miles and behaving faultlessly (touch wood) Oil checked weekly but have not needed to top up since service.. New front runflats fitted by dealer before I bought. I replaced rear runflats in May - lots of tread left but sidewall starting to "wrinkle with age" Great service from local dealer who supplied and fitted new bridgestones runflats for £384 for the pair. I've had Discoveries and Freelanders in the past and they were a nightmare for reliability and no backing from dealers once out of warranty. I feel happy that if I do get serious engine issues I can rely on Toyoyta to put them right within the seven year period. Some peace of mind that I doubt you'd get with many other brands. I've also owned other Toyotas including two Prius and Aygo's for the missus and ale have been faultless.

[CharlieFarlie]

I see Nmaria said "from an early stage oil consumption was excessive".

Could be a good question too, as I believe a few were like this. My 57 plate has never used ANY oil between services, perhaps that's a sign of no issues? (bit of wishf thinking perhaps!)

So question is- have all the engine swappers always used oil from day one and it's just a case of when they escalate into a problem? In a way I hope so, as this would be a tell sign of which will need swapping.

Dave

There are cars from the early 2006 up to the SR180s in 2009 that have had the problems...

A Friends Son has a 2009 SR and was telling Me about its thirst for oil to the point he was putting 1.5 litres in every 800 miles or so.

When I got My car it burnt NO oil at all for around the first 15,000 miles. It then simply started drinking the stuff... Why ? Haven't a clue .....

Remember also the first replacement engine also did 6 or 7 thousand before it to started to drink.......

At one time I was thinking that the common mileage was around 50K when issues started.. But Dons old car was at 20K and others have posted around 30K.

[anchorman]

No Charlie, my car didn't start using oil at 20k it did it from new like most of the early ones did but they soon got it sorted. I've not come across any 2009s in all the ones I've heard of.

[anchorman]

Who on earth has put another 2012 in?

The year is when the vehicle was produced not when the engine was fitted. Would the two posters of 2012 mind clarifying what the situation is. Is it an error posting or were 2012 models fitted with new engines?

[Gods_gift]

The question phrasing is a bit squify "What year was your car when the engine was changed?" Should it not say "what year was your car originally produced?"

[CharlieFarlie]

No Charlie, my car didn't start using oil at 20k it did it from new like most of the early ones did but they soon got it sorted. I've not come across any 2009s in all the ones I've heard of.

What I meant was was that Your engine or should I say the engine in your old car was changed at 20,000 ..................

[anchorman]

I know. I was referring to my old engine. They (early models) used oil from the start, it isn't something that just breaks.

[CharlieFarlie]

I know. I was referring to my old engine. They (early models) used oil from the start, it isn't something that just breaks.

Now I am confused....

If the early models all burn oil the all of them will qualify for a replacement ??

My car when I first got it did Not burn any oil at all !! It then developed an appetite for the stuff...

What You are saying Don is that all early engines need replacement ???

[anchorman]

There is such a misunderstanding of this subject.

All of the bulletins (including your own sticky Charlie) describe how early engines are prone to burning oil.

The problem of burning oil was due to the design of the early oil scraper rings. The oil scraper ring is one of the 3 piston rings that make the piston a good seal in the bore. The top 2 are merely compression rings and the bottom one is to stop oil from making its way from the sump into the upper cylinder and getting burned along with the fuel and air mix.

In the first engines this oil ring didn't do a good job. Oil would indeed get burned and there were several side effects;

1. The added carbon from this oil burning could clog up the EGR

2. The added carbon could also clog up the DPNR on the T180s or the cat' on the 136's.

3. In some rarer cases the carbon build up could attack the cylinder head gasket which could be exacerbated if it reacted with the coolant.

Where the big misunderstanding lies is that engines per se did not fail as such. If you read my example above it tells you that the engine was changed to improve the situation. It is more a matter of convenience that it stopped the oil consumption and therefor the long term risk to the other components. If Toyota had not have been so noble and it had not have been changed, it would still be running. The current owner would still be adding oil frequently and this applies to ALL of the engines that I have known or assisted with. Not one single one failed as such. I.e something doesn't break inside and are quite capable of lasting just as long as any rival engine.

Right, so lets think about the variations. Depending on such things as;

1. Driving style

2. The annual mileage

3. The type of engine oil used (fully synthetic is worse because it is able to cling to the cylinder walls better)

4. The type of fuel being used and there is lots of evidence to suggest that supermarket fuels which are low on cleaning additives are the worst...........

The problem of oil consumption could cause knock on effects to the ancillary components listed above. However, it isn't a given and many engines that didn't have the worst case stack of adverse conditions are still serviceable. Do they use oil? Yes of course because nothing has changed. Are the owners bothered? No in many cases because the duty cycle doesn't manifest any of the possible problems - they take regular topping up as normal just like all the Honda CRV owners and many others too numerous to mention.

So why did your engine start using oil Charlie? Well the time taken to do the evaluation was way too short to start with but as stated above, it could be down to all those factors. My old red one was variable and sometimes it could catch me out and be very low on the stick and others it seemed to hardly move when I expected it to do so.

So why then are Toyota being so generous and giving us engines we don't really need? It is because they have a legal and moral obligation of a test of reasonableness (yes the term really does exist). In this case owners will expect that the vehicle should behave in a predictable manner for a reasonable period of time. In some cases they do not and if the above conditions stack up then owners might be faced with excessive costs in what might be considered an unreasonably short period of ownership - not necessarily down to the oil consumption but because of something that failed as a result of it. For this reason the warranty has to have an end date and mileage that is reasonable and fair. It isn't set to confound those that haven't been smart enough to jump on the bandwagon but in a court and in reality it is fair to say that if a problem has not shown itself in 7 years or 112,000 miles then it isn't likely to and in any case by this time you have to factor in normal wear and tear.

It is entirely reasonable and not at all the injustice they are accused of. How long can they be expected to underwrite a vehicle? From what I can see the majority are perfectly happy now their vehicles have been reworked. They do not feel at risk and are eternally grateful to be so lucky. Should there have been a recall? No absolutely not. The risks have been calculated and the method of getting affected owners back to a position where they can be reworked are sufficient. The information is made available to the independant motor trade if they only think to check. If there is a weakness it is with some of the Toyota dealers in not researching the situation and go off ripping engines apart when the policy is to replace it.

They let the side down not TGB/Toyota.

For these very reasons I am more confident about owning a Toyota/RAV4 than any other brand including the so called German top marques. Nobody will convince me otherwise.

So there!

[three5]

There is such a misunderstanding of this subject.

All of the bulletins (including your own sticky Charlie) describe how early engines are prone to burning oil.

The problem of burning oil was due to the design of the early oil scraper rings. The oil scraper ring is one of the 3 piston rings that make the piston a good seal in the bore. The top 2 are merely compression rings and the bottom one is to stop oil from making its way from the sump into the upper cylinder and getting burned along with the fuel and air mix.

In the first engines this oil ring didn't do a good job. Oil would indeed get burned and there were several side effects;

1. The added carbon from this oil burning could clog up the EGR

2. The added carbon could also clog up the DPNR on the T180s or the cat' on the 136's.

3. In some rarer cases the carbon build up could attack the cylinder head gasket which could be exacerbated if it reacted with the coolant.

Where the big misunderstanding lies is that engines per se did not fail as such. If you read my example above it tells you that the engine was changed to improve the situation. It is more a matter of convenience that it stopped the oil consumption and therefor the long term risk to the other components. If Toyota had not have been so noble and it had not have been changed, it would still be running. The current owner would still be adding oil frequently and this applies to ALL of the engines that I have known or assisted with. Not one single one failed as such. I.e something doesn't break inside and are quite capable of lasting just as long as any rival engine.

Right, so lets think about the variations. Depending on such things as;

1. Driving style

2. The annual mileage

3. The type of engine oil used (fully synthetic is worse because it is able to cling to the cylinder walls better)

4. The type of fuel being used and there is lots of evidence to suggest that supermarket fuels which are low on cleaning additives are the worst...........

The problem of oil consumption could cause knock on effects to the ancillary components listed above. However, it isn't a given and many engines that didn't have the worst case stack of adverse conditions are still serviceable. Do they use oil? Yes of course because nothing has changed. Are the owners bothered? No in many cases because the duty cycle doesn't manifest any of the possible problems - they take regular topping up as normal just like all the Honda CRV owners and many others too numerous to mention.

So why did your engine start using oil Charlie? Well the time taken to do the evaluation was way too short to start with but as stated above, it could be down to all those factors. My old red one was variable and sometimes it could catch me out and be very low on the stick and others it seemed to hardly move when I expected it to do so.

So why then are Toyota being so generous and giving us engines we don't really need? It is because they have a legal and moral obligation of a test of reasonableness (yes the term really does exist). In this case owners will expect that the vehicle should behave in a predictable manner for a reasonable period of time. In some cases they do not and if the above conditions stack up then owners might be faced with excessive costs in what might be considered an unreasonably short period of ownership - not necessarily down to the oil consumption but because of something that failed as a result of it. For this reason the warranty has to have an end date and mileage that is reasonable and fair. It isn't set to confound those that haven't been smart enough to jump on the bandwagon but in a court and in reality it is fair to say that if a problem has not shown itself in 7 years or 112,000 miles then it isn't likely to and in any case by this time you have to factor in normal wear and tear.

It is entirely reasonable and not at all the injustice they are accused of. How long can they be expected to underwrite a vehicle? From what I can see the majority are perfectly happy now their vehicles have been reworked. They do not feel at risk and are eternally grateful to be so lucky. Should there have been a recall? No absolutely not. The risks have been calculated and the method of getting affected owners back to a position where they can be reworked are sufficient. The information is made available to the independant motor trade if they only think to check. If there is a weakness it is with some of the Toyota dealers in not researching the situation and go off ripping engines apart when the policy is to replace it.

They let the side down not TGB/Toyota.

For these very reasons I am more confident about owning a Toyota/RAV4 than any other brand including the so called German top marques. Nobody will convince me otherwise.

So there!

Hi Don,

as usual a well-reasoned and explained case for why we are where we are. I’m full of admiration!!!! I wouldn't argue with a word of it but I'm still thinking about why some cars are a problem and others are not. As I’ve said previously on the forum, my brother and I bought two, identical in every respect XT5’s, from the same dealer on the same day in 2008. His motor is now in the tender(ish) care of my daughter and uses minute quantities of oil, averages mid to high 40’s MPG and has 50k + on the odometer whilst acting as the family workhorse.

What do you think about the following reasoning:

Modern diesel engines are a far cry from the 2 1/4 litre units that powered the LR 2A and 3 in the 1970's. That engine produced approximately 70 BHP and revved to 2500 rpm. As a matter of interest it had 3 compression rings and a scraper ring. The 2.2D-4D engine even in its earlier form has an almost identical capacity but an entirely different performance. 137 BHP and it revs comfortably to 4500 RPM and quite safely well beyond that, BUT it only has 2 compression rings and an oil control ring. How has this been done?

Electronics in the form of fuel system control and engine management provide much of this increase in output but that is not the whole story. The machine tools used to produce the engines have changed just as much as the engines themselves, they too benefit from electronic control and measuring and work to accuracies of a few microns rather than the “couple of thou” of the ‘70’s, even in a mass production environment. They also have far superior cutting tools – the use of cermet is almost universal. Designers use this extra accuracy to good effect in reducing component tolerances. ( As a brief aside, a turbo shaft would have an accuracy of something like +/- 5 microns. ) I don’t know what the combined production tolerance on the cylinder bores/pistons is on the D-4D but it won’t be any more than the combined design/production engineers at Toyota can achieve reliably, and herein lies the difficulty. The days of selective assembly are long gone, each component has to be produced to a very high standard of accuracy – and they are. However, because nothing is perfect, a tolerance is still required and although these are very small the possibility of a maximum size bore combined with a minimum size piston still exists. It is my belief that the statistically small number of engines produced at this end of the tolerance band are the ones exhibiting the problems and it is also the reason why not all engines are affected.

The extra power produced by the 180 engine should, in theory, exacerbate this problem as you have to burn more fuel to produce the extra BHP and I wonder if this is part of the reason for the demise of the 180 engine? The newer 150 engine seems bombproof and in my mind ( - 150 as opposed to 137 BHP ) is evidence that Toyota have further refined the design/production processes required to manufacture this engine to a standard of reliability that they can sustain. I just wish I could justify buying one, but my top up oil remains in the drum after 3000 miles of the replacement engine!

[CharlieFarlie]

Why is it the that Members keep on saying their engine burn NO oil at all ??

Toyota are IMHO replacing the engines they have to.. And only those..

They will of course not issue a recall on the cars simply because it is not a safety issue..

What they are doing is just replacing those that are recognised and brought to their attention.....

They will be doing this to avoid another debacle like the one with the brake issue of a couple of Years ago....

It could be argued that Toyota IF they know what the problem is should simply recall All vehicles fitted with "At risk" engines and sort the !Removed! things out once and for all... Instead they have adopted a half way house type policy where only those that recognise the problem or take them to a cooperative dealer will mean the cars are sorted.

Many Folk have paid out large sums of hard earn t coin for repairs to EGRs DPNRs Injectors ect ect without even knowing about this problem..

A friends Son had his oil go so low it buggered the Turbo. Yes of course He should have checked the oil but he was abroad (France) on holiday when the car wet !Removed! up... Toyota charged around 2K to replace the turbo.. Then He mentioned it to Me as a fellow Rav owner.. In no time at all the engine was oil consumption tested and engine replaced.....

OK job done but He still lost 2K for the turbo replacement that would not have occurred if the problem had not been there in the first place.. Mark however appreciates that he should have checked the oil more often.. It was burning at a rate of just over 2 litres per 1000 miles.....

For the record Marks car is a 2009 SR 180. Mileage at time of engine change 42.000

The fact remains that once the extended warranty runs out theses cars will continue to surface and Owners will be left with a bill likely greater than the car is worth...

[CharlieFarlie]

There is such a misunderstanding of this subject.

All of the bulletins (including your own sticky Charlie) describe how early engines are prone to burning oil.

The problem of burning oil was due to the design of the early oil scraper rings. The oil scraper ring is one of the 3 piston rings that make the piston a good seal in the bore. The top 2 are merely compression rings and the bottom one is to stop oil from making its way from the sump into the upper cylinder and getting burned along with the fuel and air mix.

In the first engines this oil ring didn't do a good job. Oil would indeed get burned and there were several side effects;

1. The added carbon from this oil burning could clog up the EGR

2. The added carbon could also clog up the DPNR on the T180s or the cat' on the 136's.

3. In some rarer cases the carbon build up could attack the cylinder head gasket which could be exacerbated if it reacted with the coolant.

Where the big misunderstanding lies is that engines per se did not fail as such. If you read my example above it tells you that the engine was changed to improve the situation. It is more a matter of convenience that it stopped the oil consumption and therefor the long term risk to the other components. If Toyota had not have been so noble and it had not have been changed, it would still be running. The current owner would still be adding oil frequently and this applies to ALL of the engines that I have known or assisted with. Not one single one failed as such. I.e something doesn't break inside and are quite capable of lasting just as long as any rival engine.

Right, so lets think about the variations. Depending on such things as;

1. Driving style

2. The annual mileage

3. The type of engine oil used (fully synthetic is worse because it is able to cling to the cylinder walls better)

4. The type of fuel being used and there is lots of evidence to suggest that supermarket fuels which are low on cleaning additives are the worst...........

The problem of oil consumption could cause knock on effects to the ancillary components listed above. However, it isn't a given and many engines that didn't have the worst case stack of adverse conditions are still serviceable. Do they use oil? Yes of course because nothing has changed. Are the owners bothered? No in many cases because the duty cycle doesn't manifest any of the possible problems - they take regular topping up as normal just like all the Honda CRV owners and many others too numerous to mention.

So why did your engine start using oil Charlie? Well the time taken to do the evaluation was way too short to start with but as stated above, it could be down to all those factors. My old red one was variable and sometimes it could catch me out and be very low on the stick and others it seemed to hardly move when I expected it to do so.

So why then are Toyota being so generous and giving us engines we don't really need? It is because they have a legal and moral obligation of a test of reasonableness (yes the term really does exist). In this case owners will expect that the vehicle should behave in a predictable manner for a reasonable period of time. In some cases they do not and if the above conditions stack up then owners might be faced with excessive costs in what might be considered an unreasonably short period of ownership - not necessarily down to the oil consumption but because of something that failed as a result of it. For this reason the warranty has to have an end date and mileage that is reasonable and fair. It isn't set to confound those that haven't been smart enough to jump on the bandwagon but in a court and in reality it is fair to say that if a problem has not shown itself in 7 years or 112,000 miles then it isn't likely to and in any case by this time you have to factor in normal wear and tear.

It is entirely reasonable and not at all the injustice they are accused of. How long can they be expected to underwrite a vehicle? From what I can see the majority are perfectly happy now their vehicles have been reworked. They do not feel at risk and are eternally grateful to be so lucky. Should there have been a recall? No absolutely not. The risks have been calculated and the method of getting affected owners back to a position where they can be reworked are sufficient. The information is made available to the independant motor trade if they only think to check. If there is a weakness it is with some of the Toyota dealers in not researching the situation and go off ripping engines apart when the policy is to replace it.

They let the side down not TGB/Toyota.

For these very reasons I am more confident about owning a Toyota/RAV4 than any other brand including the so called German top marques. Nobody will convince me otherwise.

So there!

Hi Don,

as usual a well-reasoned and explained case for why we are where we are. I’m full of admiration!!!! I wouldn't argue with a word of it but I'm still thinking about why some cars are a problem and others are not. As I’ve said previously on the forum, my brother and I bought two, identical in every respect XT5’s, from the same dealer on the same day in 2008. His motor is now in the tender(ish) care of my daughter and uses minute quantities of oil, averages mid to high 40’s MPG and has 50k + on the odometer whilst acting as the family workhorse.

What do you think about the following reasoning:

Modern diesel engines are a far cry from the 2 1/4 litre units that powered the LR 2A and 3 in the 1970's. That engine produced approximately 70 BHP and revved to 2500 rpm. As a matter of interest it had 3 compression rings and a scraper ring. The 2.2D-4D engine even in its earlier form has an almost identical capacity but an entirely different performance. 137 BHP and it revs comfortably to 4500 RPM and quite safely well beyond that, BUT it only has 2 compression rings and an oil control ring. How has this been done?

Electronics in the form of fuel system control and engine management provide much of this increase in output but that is not the whole story. The machine tools used to produce the engines have changed just as much as the engines themselves, they too benefit from electronic control and measuring and work to accuracies of a few microns rather than the “couple of thou” of the ‘70’s, even in a mass production environment. They also have far superior cutting tools – the use of cermet is almost universal. Designers use this extra accuracy to good effect in reducing component tolerances. ( As a brief aside, a turbo shaft would have an accuracy of something like +/- 5 microns. ) I don’t know what the combined production tolerance on the cylinder bores/pistons is on the D-4D but it won’t be any more than the combined design/production engineers at Toyota can achieve reliably, and herein lies the difficulty. The days of selective assembly are long gone, each component has to be produced to a very high standard of accuracy – and they are. However, because nothing is perfect, a tolerance is still required and although these are very small the possibility of a maximum size bore combined with a minimum size piston still exists. It is my belief that the statistically small number of engines produced at this end of the tolerance band are the ones exhibiting the problems and it is also the reason why not all engines are affected.

The extra power produced by the 180 engine should, in theory, exacerbate this problem as you have to burn more fuel to produce the extra BHP and I wonder if this is part of the reason for the demise of the 180 engine? The newer 150 engine seems bombproof and in my mind ( - 150 as opposed to 137 BHP ) is evidence that Toyota have further refined the design/production processes required to manufacture this engine to a standard of reliability that they can sustain. I just wish I could justify buying one, but my top up oil remains in the drum after 3000 miles of the replacement engine!

Chris,, Nice write up ! Are You saying since Your engine was replaced it has burnt NO oil since it was replaced 3000 miles ago ???

[anchorman]

Some good points Chris - thank you.

I get the feeling that some people don't understand what is going on with this engine program and I wouldn't expect them to without some technical knowledge and understanding of how an engine works. What I do find alarming is how quickly it can turn into an offensive toward Toyota for their failings and the way they handle it and the question of whether cars should be recalled etc. I studied engine design in the late 70s and have worked in vehicle development since so I am aware that vehicles can get launched into the market with service issues. The reasons vary from departments meeting tight targets to suppliers not supplying in production what they supplied for testing.

Going back to your comments on tolerance stacks, I guess that has to be considered but my feeling is that they will have evaluated the worst case in testting the engine and parts at each end of the stack should still be predictable. Effectively they will Shell out pistons one after the other and they will fit the bore of any engine block consistently and within limits. I think the problem more specifically is with the design of the oil scraper ring and how ineffective it was under certain conditions. As you know, rings have to bed in and the period they take will vary depending on lots of factors.

If we think about how the engine and the problem evolved then we can follow the various steps that engineering took to address the issues as they became apparent. I will summarise just off the top of my head;

The engine was designed from scratch for a number of European models launching in 2005/6 and had to meet the requirements of current and future emmission legislation. When you think about it, an engine of 2.2 litres with outputs from 120 to 180 PS and such innovations as variable valve timing, 16 valve twin cams, common rail electronic/piezo injection, contra rotating balance shafts etc, it was a big step forward from the previous (although fully evolved) 2.0 litre unit. As I have said before, even compared to the various efforts of other manufacturers it is a triumph of engine design but this is not understood by someone with no feel for what was done (understandably). It was the equivalent of a Typhoon fighter being the replacement for a Sopwith Camel.

Now we get to the stage where this has to be introduced into the market place. Any development engineer would like the luxury of time and resource to evaluate a product but ask poor old shcm who is still in the thick of it. In reality, there is a limit to what can be done and you have to accept that real test is out in the field - that means that we complete the development testing and in some cases modifications are needed.

The first sign that something wasn't right was owners noticing EGRs starting to stick. I believe the first one here was with Sywy and his T180. At about the same time we were noticing that vehicle were getting an ECU flash when they were in for service. This would have been the early indications that something was wrong. What TGB were doing was attempting to mitigate the effects by altering the fuel mapping - a reasonable interim approach. Meanwhile back at the ranch (European Product Development) it would have been dawning on them that this needed something more fundamental to "nip it in the bud". At that time, production were still building engines that consumed oil. The fixes came thick and fast. The dealerships were fixing engines by fitting a modified oil scraper (a labourious process which is more time consuming than changing the engine and requiring the best mechanic in the dealership) and production was fitting modied parts from new. Obviously the new engines take time to work through, the volume of engines being reworked at dealers was starting to justify an engine swap. You can follow this process by reading the various TSBs that charter the evolution of the current spec. The engines now have different pistons, completely new ring arrangement, all new sealing of the cylinder head etc.

The problem for Toyota in the wake of all the bad press that came from sticky pedals was to come up with a satisfactory way of dealing with it all. Despite what some of the more sceptical would suggest, the production issues were solved by May 2008. The oil consumption was actually solved earlier but when you have cars on ships and in dealerships it isn't easy and the best way of sorting it out is to sell them and see whether the the owner and his operating conditions throw up a problem. They don't really have an option. Even if they turn a ship around and send it back, they only have facilities for building cars in Japan, not for stripping them down again. This is no different than any other manufacturer would do it.

For those that understand (and I know you and several others do Chris), I reiterate, the engine design is fundamentally ground breaking.

The back up is unrivaled.

We are in good hands and I'm staying.

[Gods_gift]

Why don't we have a like button!

[three5]

There is such a misunderstanding of this subject.

All of the bulletins (including your own sticky Charlie) describe how early engines are prone to burning oil.

The problem of burning oil was due to the design of the early oil scraper rings. The oil scraper ring is one of the 3 piston rings that make the piston a good seal in the bore. The top 2 are merely compression rings and the bottom one is to stop oil from making its way from the sump into the upper cylinder and getting burned along with the fuel and air mix.

In the first engines this oil ring didn't do a good job. Oil would indeed get burned and there were several side effects;

1. The added carbon from this oil burning could clog up the EGR

2. The added carbon could also clog up the DPNR on the T180s or the cat' on the 136's.

3. In some rarer cases the carbon build up could attack the cylinder head gasket which could be exacerbated if it reacted with the coolant.

Where the big misunderstanding lies is that engines per se did not fail as such. If you read my example above it tells you that the engine was changed to improve the situation. It is more a matter of convenience that it stopped the oil consumption and therefor the long term risk to the other components. If Toyota had not have been so noble and it had not have been changed, it would still be running. The current owner would still be adding oil frequently and this applies to ALL of the engines that I have known or assisted with. Not one single one failed as such. I.e something doesn't break inside and are quite capable of lasting just as long as any rival engine.

Right, so lets think about the variations. Depending on such things as;

1. Driving style

2. The annual mileage

3. The type of engine oil used (fully synthetic is worse because it is able to cling to the cylinder walls better)

4. The type of fuel being used and there is lots of evidence to suggest that supermarket fuels which are low on cleaning additives are the worst...........

The problem of oil consumption could cause knock on effects to the ancillary components listed above. However, it isn't a given and many engines that didn't have the worst case stack of adverse conditions are still serviceable. Do they use oil? Yes of course because nothing has changed. Are the owners bothered? No in many cases because the duty cycle doesn't manifest any of the possible problems - they take regular topping up as normal just like all the Honda CRV owners and many others too numerous to mention.

So why did your engine start using oil Charlie? Well the time taken to do the evaluation was way too short to start with but as stated above, it could be down to all those factors. My old red one was variable and sometimes it could catch me out and be very low on the stick and others it seemed to hardly move when I expected it to do so.

So why then are Toyota being so generous and giving us engines we don't really need? It is because they have a legal and moral obligation of a test of reasonableness (yes the term really does exist). In this case owners will expect that the vehicle should behave in a predictable manner for a reasonable period of time. In some cases they do not and if the above conditions stack up then owners might be faced with excessive costs in what might be considered an unreasonably short period of ownership - not necessarily down to the oil consumption but because of something that failed as a result of it. For this reason the warranty has to have an end date and mileage that is reasonable and fair. It isn't set to confound those that haven't been smart enough to jump on the bandwagon but in a court and in reality it is fair to say that if a problem has not shown itself in 7 years or 112,000 miles then it isn't likely to and in any case by this time you have to factor in normal wear and tear.

It is entirely reasonable and not at all the injustice they are accused of. How long can they be expected to underwrite a vehicle? From what I can see the majority are perfectly happy now their vehicles have been reworked. They do not feel at risk and are eternally grateful to be so lucky. Should there have been a recall? No absolutely not. The risks have been calculated and the method of getting affected owners back to a position where they can be reworked are sufficient. The information is made available to the independant motor trade if they only think to check. If there is a weakness it is with some of the Toyota dealers in not researching the situation and go off ripping engines apart when the policy is to replace it.

They let the side down not TGB/Toyota.

For these very reasons I am more confident about owning a Toyota/RAV4 than any other brand including the so called German top marques. Nobody will convince me otherwise.

So there!

Hi Don,

as usual a well-reasoned and explained case for why we are where we are. I’m full of admiration!!!! I wouldn't argue with a word of it but I'm still thinking about why some cars are a problem and others are not. As I’ve said previously on the forum, my brother and I bought two, identical in every respect XT5’s, from the same dealer on the same day in 2008. His motor is now in the tender(ish) care of my daughter and uses minute quantities of oil, averages mid to high 40’s MPG and has 50k + on the odometer whilst acting as the family workhorse.

What do you think about the following reasoning:

Modern diesel engines are a far cry from the 2 1/4 litre units that powered the LR 2A and 3 in the 1970's. That engine produced approximately 70 BHP and revved to 2500 rpm. As a matter of interest it had 3 compression rings and a scraper ring. The 2.2D-4D engine even in its earlier form has an almost identical capacity but an entirely different performance. 137 BHP and it revs comfortably to 4500 RPM and quite safely well beyond that, BUT it only has 2 compression rings and an oil control ring. How has this been done?

Electronics in the form of fuel system control and engine management provide much of this increase in output but that is not the whole story. The machine tools used to produce the engines have changed just as much as the engines themselves, they too benefit from electronic control and measuring and work to accuracies of a few microns rather than the “couple of thou” of the ‘70’s, even in a mass production environment. They also have far superior cutting tools – the use of cermet is almost universal. Designers use this extra accuracy to good effect in reducing component tolerances. ( As a brief aside, a turbo shaft would have an accuracy of something like +/- 5 microns. ) I don’t know what the combined production tolerance on the cylinder bores/pistons is on the D-4D but it won’t be any more than the combined design/production engineers at Toyota can achieve reliably, and herein lies the difficulty. The days of selective assembly are long gone, each component has to be produced to a very high standard of accuracy – and they are. However, because nothing is perfect, a tolerance is still required and although these are very small the possibility of a maximum size bore combined with a minimum size piston still exists. It is my belief that the statistically small number of engines produced at this end of the tolerance band are the ones exhibiting the problems and it is also the reason why not all engines are affected.

The extra power produced by the 180 engine should, in theory, exacerbate this problem as you have to burn more fuel to produce the extra BHP and I wonder if this is part of the reason for the demise of the 180 engine? The newer 150 engine seems bombproof and in my mind ( - 150 as opposed to 137 BHP ) is evidence that Toyota have further refined the design/production processes required to manufacture this engine to a standard of reliability that they can sustain. I just wish I could justify buying one, but my top up oil remains in the drum after 3000 miles of the replacement engine!

Chris,, Nice write up ! Are You saying since Your engine was replaced it has burnt NO oil since it was replaced 3000 miles ago ???

Charlie - since the engine was replaced, I've added no oil. OK, the level might have dropped marginally ( 3 - 4 mm on dipstick maybe ), but not enough to make it worth topping up since I will be changing the oil next month before a drive to Switzerland, southern France and back. I'm still a bit obsessive about checking it though!

The point I was trying to make was that all engines are not affected so there is no justification for a general recall from Toyota. It is my belief that only a small fraction of production, where the pistons are right at the lower end of the tolerance and bores are right at the upper end, have proved a problem. Don refers to Testing and Development and, as someone who worked in R&D for the greater part of my career, he has never said a truer word. Unless the organisation is very different to all the ones I have experience of, there will be a bunch of sales/marketing/accountants at Toyota who are pushing the Development Engineers to shorten the testing process to a minimum as engines under test are generating no cashflow/profit for the company. This is just plain old economics. The Engineers ( mea culpa! ) would prefer to test everything, probably several times , until they were totally convinced that everything was as near perfect as they could get it. The rest of the company are pushing to make testing a risk reduction exercise rather than a perfect(ish) science of risk elimination. If I was a betting man, which I'm not, I would be putting my money on the new design of oil scraper ring being more tolerant of size variation than the initial version. The original design was fine for the vast majority of production but the new one, possibly combined with a miniscule tolerance change, covers almost all cases. I say almost all because as human beings we ain't done anything perfect yet and I can see no prospect of us achieving it in the forseeable future. If Microsoft were to test Windows 8 to the point where they knew absolutely that there were no possible bugs or security weaknesses with it, it wouldn't be released till about the year 8000!

[anchorman]

My new 150 that I had in 2010 used no oil in the 4000 miles up to me (foolishly) selling it.

My current 150 has used no oil since I changed it nearly 4000 miles ago.

Maybe the oil scraper rings are the same. I know that the 3/4 engines have newer design pistons than the first 2006 models - they could well be the same too.

At first I though mine did use a bit but left overnight it is just above the top mark and not even black yet.

[Gods_gift]

Anyideas what the difference is between the 137bhp units and the 150's in terms of parts? Does the 150 have a different mapping or turbo?

[CharlieFarlie]

Some good points Chris - thank you.

I get the feeling that some people don't understand what is going on with this engine program and I wouldn't expect them to without some technical knowledge and understanding of how an engine works. What I do find alarming is how quickly it can turn into an offensive toward Toyota for their failings and the way they handle it and the question of whether cars should be recalled etc. I studied engine design in the late 70s and have worked in vehicle development since so I am aware that vehicles can get launched into the market with service issues. The reasons vary from departments meeting tight targets to suppliers not supplying in production what they supplied for testing.

Going back to your comments on tolerance stacks, I guess that has to be considered but my feeling is that they will have evaluated the worst case in testting the engine and parts at each end of the stack should still be predictable. Effectively they will shell out pistons one after the other and they will fit the bore of any engine block consistently and within limits. I think the problem more specifically is with the design of the oil scraper ring and how ineffective it was under certain conditions. As you know, rings have to bed in and the period they take will vary depending on lots of factors.

If we think about how the engine and the problem evolved then we can follow the various steps that engineering took to address the issues as they became apparent. I will summarise just off the top of my head;

The engine was designed from scratch for a number of European models launching in 2005/6 and had to meet the requirements of current and future emmission legislation. When you think about it, an engine of 2.2 litres with outputs from 120 to 180 PS and such innovations as variable valve timing, 16 valve twin cams, common rail electronic/piezo injection, contra rotating balance shafts etc, it was a big step forward from the previous (although fully evolved) 2.0 litre unit. As I have said before, even compared to the various efforts of other manufacturers it is a triumph of engine design but this is not understood by someone with no feel for what was done (understandably). It was the equivalent of a Typhoon fighter being the replacement for a Sopwith Camel.

Now we get to the stage where this has to be introduced into the market place. Any development engineer would like the luxury of time and resource to evaluate a product but ask poor old shcm who is still in the thick of it. In reality, there is a limit to what can be done and you have to accept that real test is out in the field - that means that we complete the development testing and in some cases modifications are needed.

The first sign that something wasn't right was owners noticing EGRs starting to stick. I believe the first one here was with Sywy and his T180. At about the same time we were noticing that vehicle were getting an ECU flash when they were in for service. This would have been the early indications that something was wrong. What TGB were doing was attempting to mitigate the effects by altering the fuel mapping - a reasonable interim approach. Meanwhile back at the ranch (European Product Development) it would have been dawning on them that this needed something more fundamental to "nip it in the bud". At that time, production were still building engines that consumed oil. The fixes came thick and fast. The dealerships were fixing engines by fitting a modified oil scraper (a labourious process which is more time consuming than changing the engine and requiring the best mechanic in the dealership) and production was fitting modied parts from new. Obviously the new engines take time to work through, the volume of engines being reworked at dealers was starting to justify an engine swap. You can follow this process by reading the various TSBs that charter the evolution of the current spec. The engines now have different pistons, completely new ring arrangement, all new sealing of the cylinder head etc.

The problem for Toyota in the wake of all the bad press that came from sticky pedals was to come up with a satisfactory way of dealing with it all. Despite what some of the more sceptical would suggest, the production issues were solved by May 2008. The oil consumption was actually solved earlier but when you have cars on ships and in dealerships it isn't easy and the best way of sorting it out is to sell them and see whether the the owner and his operating conditions throw up a problem. They don't really have an option. Even if they turn a ship around and send it back, they only have facilities for building cars in Japan, not for stripping them down again. This is no different than any other manufacturer would do it.

For those that understand (and I know you and several others do Chris), I reiterate, the engine design is fundamentally ground breaking.

The back up is unrivaled.

We are in good hands and I'm staying.

Firstly let Me say Im in absolute agreement with GG on the thanks button thing..

Cracking write up Don and one that ole dyslexic here had to read 2 or three times..

But I stand by what I said above in that if a recognised design fault or quality control issue is made then all cars affected should be recalled and fixed ...

It should not have to be the cars that are displaying problems Inside of warranty extended or otherwise that are fixed. It should be the entire production run...

Quote Don..

What I do find alarming is how quickly it can turn into an offensive toward Toyota for their failings and the way they handle it and the question of whether cars should be recalled etc

Unquote..

since that was clearly aimed at me I shall reply...

sI have always praised Toyota for the fantastic service and back up I have been given,,,, BUT I do feel this is a patch and not a total fix.... It is quite obvious that after warranty expires that people will have problems.. Problems due to poor quality design or quality control.

Don You repeat time and time again that you are completely happy and think that Toyota are some sort of Gods... Your last comment "We are in good hands and I'm staying. " Well of course You can say that You do NOT own an affected vehicle !! So Your comments are really NOT relevant to those that do !!

what would be Your answer to someone You advise to ignore the facts and buy an at risk car if they come back after warranty has expired and engine has gone awol ?? Guidance ???

Sorry Matey but You are not the one with an at risk car !!

[DjRav]

As someone mentioned the LR 2-1/4, I just thought I'd mention- (as I was an owner some years ago), it is the only car I've ever had that I ACTUALLY spent longer fixing than driving. No exageration, total man hours fixing (me/others) added up to more than the hours spent chugging along!

And the head blew btw (and had to be skimmed)

Dave

[anchorman]

If somebody asked me about buying a 2006 car in 2013 I would advise them to find out if it has had an engine change or if it had used oil. If I suspected that it hadn't or couldn't reliably find out about oil consumption I would tell them that there is a risk that it could use oil and there might be a knock on effect to other components.

As we haven't got to 2013 I would tell them to buy it if they like it and it fits the bill and if they come across any problems with any of the above that they need not worry as they can get it sorted FOC. I have no reservations about telling somebody to buy yours but you have mooted several times that cars cannot be trusted even if they have had the work done. I know that some of this comes from your experience but apart from Mistermena who's dealer did what they shouldn't have done, nobody else has had a similar problem or is worried about it.

The cars in the survey above are weighted pretty much as I expected. The majority from 2006, a lessor amount in 2007 and a few in 2008. From this info I feel more confident in telling a potential owner that there is some risk with a 2007, a small risk with a 2008 and virtually no risk with a 2009. If they do find that they get a problem they have ubtil 2014, 2015 and 2016 to get it resolved.

I just thought I would have a quick google on oil consumption and found this for Honda CRV amongst many other;

http://www.honestjohn.co.uk/forum/post/index.htm?t=54449

http://www.hondawebsite.co.uk/forum/post5315.html

http://www.crvownersclub.com/forums/14-problems-issues/5093-oil-consumption.html

You get similar results for most makes. If these vehicles are using oil they are prone to the same problems with EGRs and DPNRs that RAVs are. Should we be advising against buying those too? Maybe Honda will sort them out I don't know but if not they will have to keep adding oil and fixing associated problems. The problem isn't unique but at least we get some help.

Other beside you Charlie have questioned why the vehicles are not recalled. I may not have an affected vehicle but I wouldn't knowingly give somebody bad advice either. I tend to try and help people where I can. The owner of my old car is a close friend but I would have had no problem selling him the car with or without the new engine. If circumstances were different I might still have it and the same would apply. Of course I am happy that it is now behaving like a new one in terms of oil consumption. Its just more convenient because he aint the best at checking as he should.

[three5]

As someone mentioned the LR 2-1/4, I just thought I'd mention- (as I was an owner some years ago), it is the only car I've ever had that I ACTUALLY spent longer fixing than driving. No exageration, total man hours fixing (me/others) added up to more than the hours spent chugging along!

And the head blew btw (and had to be skimmed)

Dave

I know exactly what you mean Dave. With mine ( 4 of them over time + 1 works vehicle ) I only ever had one actual breakdown that stopped me getting home and that was a spline failure on a Fairy Overdrive unit, however, they did seem to require a lot of keeping up with. I did find them easy to work on though, even if taking out the seat box was a bit tedious. I've still got the full workshop manual AND parts catalogue. I can't imagine there were many vehicles where you could actually buy a copy of the parts catalogue, perhaps that says something. 'Still have a great affection for them though even if I would no longer contemplate them as an everyday vehicle.

[CharlieFarlie]

Time and time again other brands or models are put up as a smoke screen to these topics......

But We are talking Rav4 here because this is after all a Rav4 Forum......

As I don't own a Land-rover or a Honda what goes on with them is of no importance to Me whatsoever. Sorry if that sounds selfish but it just isn't !