D4D Engine Issues, What Are They Really ?

[Country_Est]

Ok so I have bought an 06 one 4.3 with the possiblity of impending engine failure.

Now I have recently read a lot about this on the forum, and about the extended warenty and replacing the engine if it uses more than 1tl or per 1000 mile (or km), and possible using coolent, but havent actually worked out what the cause of this is, piston rings have been mentioned.

Now I have been about engines for a while, and know that the oil and water wont mix well, but cant just disapear either, so I have not heard about any excessive white smoke (water), or blue smoke (oil), or even Black smoke (un-urnt fuel) beiing any sort of early tell tale signs. And the fact the oil is being used means its not mixing with the water in the cyliner head, or oil in the coolent so not sure what is going on.

So what is the issues with the engines, and if I just keep putting in more oil and water if reqd what will happen in the end.

1tr / 1000 miles = free oil change :-) every 5000 miles, just what I do as service interval on my old Frontera.

Trev

[Big Kev]

Oh Golly Gosh........ah'm too young for this......lol. Scalpel.......

[Awebb180]

To save Big Kev doing something daft ill just leave this here http://www.toyotaownersclub.com/forums/topic/132178-charliefarlies-guide-to-the-toyota-2ad-diesel-engine-and-its-issues/

Alex

[Country_Est]

Yes I read what charlie had put, carbon clogging means mr T uesd to repleace engines, mine is now out of warrenty, and I would like to know where the carbon clogging is comming from, I relaise this is probably from the EGR system chucking crap into the inlet manifold and trying to run better with less emmissions but failing completley instead.

Now my fronty has a simmialr caboning issue but the fix is carb cleaner on the EGR, down the manifold and clean the butterfly valves.

What I am trying to understand is the thinking behind the "5th injector" on a 4 cyl engine, where is it, does it really inject diesel and to where ?

Can the egr be blanked off or does the ecu throw a wobbly cos it doesnt get the right signals.

Does this carboning cause head gasket failure, if so why a 3/4 engine replacement what else is is wrong in there ?.

What happened to all the engines taken out, can I have one to start rebuilding now ready for the time I need it ?

Does anybody know the % of engines replaced against those out there working fine.

What happens to my engine if I just keep topping up the oil, will it finally thorw a rod thru the side into my guts or just not start one day.

[silly sausage]

Oh Golly Gosh........ah'm too young for this......lol. Scalpel.......

Are you ok Kev ?, I hope you've not done anything 'silly' ! Knowing how fragile and sensitive you are I'm concerned, post something below, even if you manage to just press one key, then lie down with something damp on your forehead.

[anchorman]

I'm surprised you have so many questions if you have read the above thread and are familiar with engines.

The very first 2AD engines (of which you have one) had pistons and rings that would let large amounts of oil into the upper cylinder and therefor burned oil. There was some smoke especially when cold but it reduced when hot. Soon after the start of production, the 4.3s received a series of changes which included new pistons, rings and other mods to improve the sealing internally and externally. These pretty much complete by mid to late 2008 and so engines produced from 2007 to the end of 2008 were effected to a deminishing amount to in many cases no measurable consumption. There may be odd exceptions.

The result of the oil consumption was a build up of carbon inside the engine and in all cases this was exacerbated by the use of "supermarket fuel" and the duty level - low mileage being worse than high. It could cause contamination of the head gasket and subsequent failure. It did cause EGR blockage and on D-CAT engines, DPF and cat failure in bad cases. Early attempts by dealers to strip and rebuild the engine were almost certain to lead to failure so the engines were taken in house and remanufactured as a 3/4 unit which was an almost perfect success rate but there were a few exceptions too.

There is a 5th injector mounted on the end of the block on D-CAT engines only. It sprays neat fuel into the exhaust under certain load conditions to activate the D-CAT process.

You might get hold of a second hand engine from a scrap yard/breakers but if you are thinking you will get one from a vehicle being reworked by Toyota you should know better.

[CharlieFarlie]

In short IF your engine should go awol then it will eventually drop into limp mode .. So my understanding is that there is no getting away from the problem.. If it were as simple as just putting oil in then Toyota would not be spending millions swapping units....

This complicated engine is apparently a very hard unit to strip and rebuild and was beyond even the Dealer techs resulting in failures of dealer rebuilt engines.. So unless you are of the very highest caliber mechanic wise which with respect your questions indicate not then leave it well alone !

There is no questioning that all these engines carry a fairly high risk factor... Unfortunately.... But if its working fine and well then calculate the risk and affordability IF it goes wrong and either sell the car or carry on as normal,,,,,,,

Edited to add.. These engines are subject to a HUGE deposit which the dealers would loose if they fail to return to the parent company (Toyota).. So no chance of getting one of those. Engines go back to japan for assessment as to whether they will be re-manufactured or presumably scrapped....

[Big Kev]

Ah'm fine, Paul......just the suspension on these ambulances is like Bothy's Mk.1 Rav........

And in case anybody takes the levity as being facetious, nobody has more sympathy than me for folks who find themselves with this out of warranty scenario......it was always at the back of my mind, but not a major sway, when I was getting rid of my SR180.

But it looks like Charlie's excellent Pinned article can cause as many questions as answers.....?

Big Kev.

[CharlieFarlie]

Ah'm fine, Paul......just the suspension on these ambulances is like Bothy's Mk.1 Rav........

And in case anybody takes the levity as being facetious, nobody has more sympathy than me for folks who find themselves with this out of warranty scenario......it was always at the back of my mind, but not a major sway, when I was getting rid of my SR180.

But it looks like Charlie's excellent Pinned article can cause as many questions as answers.....?

Big Kev.

Not so sure why so many questions Kev... With respect to new members reading most of the answers are there..

[Big Kev]

Ah'm fine, Paul......just the suspension on these ambulances is like Bothy's Mk.1 Rav........

And in case anybody takes the levity as being facetious, nobody has more sympathy than me for folks who find themselves with this out of warranty scenario......it was always at the back of my mind, but not a major sway, when I was getting rid of my SR180.

But it looks like Charlie's excellent Pinned article can cause as many questions as answers.....?

Big Kev.

Not so sure why so many questions Kev... With respect to new members reading most of the answers are there..

What I was euphamistically hinting at, Charlie.........

[sonixtorm]

Now I have recently read a lot about this on the forum, and about the extended warenty and replacing the engine if it uses more than 1tl or per 1000 mile (or km), and possible using coolent, but havent actually worked out what the cause of this is, piston rings have been mentioned.

Only Toyota know for sure, but I spent some time thinking about it when I had the T180. Toyota have stated that 'carbon clogging' indicates a problem in the bulletin, and I would speculate that it's either scoring of the cylinders or carbon deposit build-up on the pistons that causes premature wearing of the rings, leading to excessive oil consumption or head gasket failure in the case of the latter. It's likely a combination issue, which is why engines were failing with the dealer rebuild, and merely replacing pistons and rings won't fix every issue; I don't buy the 'it's too complex for our dealers to rebuild' line to be honest. The tendency for the EGR to suffer creeping death can't help and I am mildly astonished that it's not replaced with the newer part as a matter of course under the good will warranty extension (a flawed design is a flawed design, even if it is operating normally when the car arrives at the dealer). I also reckon the DCAT models will and do suffer far more on the way to terminal failure because they have more sensors/complexity on the exhaust side.

All just my humble opinion of course.

[CharlieFarlie]

Quote Anchorman post 6 of this very thread...........

The very first 2AD engines (of which you have one) had pistons and rings that would let large amounts of oil into the upper cylinder and therefor burned oil. There was some smoke especially when cold but it reduced when hot. Soon after the start of production, the 4.3s received a series of changes which included new pistons, rings and other mods to improve the sealing internally and externally. These pretty much complete by mid to late 2008 and so engines produced from 2007 to the end of 2008 were effected to a deminishing amount to in many cases no measurable consumption. There may be odd exceptions.

The result of the oil consumption was a build up of carbon inside the engine and in all cases this was exacerbated by the use of "supermarket fuel" and the duty level - low mileage being worse than high. It could cause contamination of the head gasket and subsequent failure. It did cause EGR blockage and on D-CAT engines, DPF and cat failure in bad cases. Early attempts by dealers to strip and rebuild the engine were almost certain to lead to failure so the engines were taken in house and remanufactured as a 3/4 unit which was an almost perfect success rate but there were a few exceptions too.

There is a 5th injector mounted on the end of the block on D-CAT engines only. It sprays neat fuel into the exhaust under certain load conditions to activate the D-CAT process.

Unquote.............

Do we need more ?? Hope not .........................................

[sonixtorm]

Quote Anchorman post 6 of this very thread...........

The very first 2AD engines (of which you have one) had pistons and rings that would let large amounts of oil into the upper cylinder and therefor burned oil. There was some smoke especially when cold but it reduced when hot. Soon after the start of production, the 4.3s received a series of changes which included new pistons, rings and other mods to improve the sealing internally and externally. These pretty much complete by mid to late 2008 and so engines produced from 2007 to the end of 2008 were effected to a deminishing amount to in many cases no measurable consumption. There may be odd exceptions.

The result of the oil consumption was a build up of carbon inside the engine and in all cases this was exacerbated by the use of "supermarket fuel" and the duty level - low mileage being worse than high. It could cause contamination of the head gasket and subsequent failure. It did cause EGR blockage

I read anchorman's post and it does explain some of the history; thanks for repeating it; but head gasket failure would ordinarily be caused by overheating (not likely the cause in this case, from what I have read) or detonation, which is a much more likely candidate given the carbon clogging. The increased pressure would be looking for the weakest link, which would either be down past the rings or the head gasket, which could feasibly weaken over time (the route via the rings could lead to more oil consumption). The EGR issue could make things much worse in this scenario as the ECU may believe the valve is closed, potentially affecting the timing of the combustion, and leading to further detonation issues.

Speculatively, given carbon accumulation (increasing compression), 'posh' diesel with its higher cetane rating could exacerbate detonation issues once clogging has begun, or at least you'd be wondering if the detergent effect of the diesel would have any benefits over the risk of detonation. This doesn't really contradict the commonly received wisdom of the forum though, as I think most would agree that once the issues have set in, there's not a lot can be done to head them off.

I am intrigued by 'head gasket contamination' though. Are you describing the cause of the failure here or the result of it? If the former I'd be interested to read some more around it as it's not a phenomenon I am familiar with.

[Davrav]

Head gasket failure related to contamination on early engines was down to a reaction between the gasket material and the coolant in use at the time I believe.

[sonixtorm]

Interesting; thanks.

[anchorman]

Head gasket failure related to contamination on early engines was down to a reaction between the gasket material and the coolant in use at the time I believe.

Exactly - that was the explanation proffered at the time. They have since changed the head gasket material and I am quite sure that the coolant that is used in 150 engines is more cerise than the redish of earlier models so maybe that has changed in production too.

A head gasket is a fairly inert thing once it is clamped up by the head so I doubt any change in compression from carbon could be significant enough to lead to failure

[kencat]

Think the main problem with the engine was Excessive back Backpressure Forcing the oil past pistons ete , Causing all sorts of problems ! Think they've modified the block now ? ( Well that's wot I think anyway , may be Wrong)

[sonixtorm]

Head gasket failure related to contamination on early engines was down to a reaction between the gasket material and the coolant in use at the time I believe.

Exactly - that was the explanation proffered at the time. They have since changed the head gasket material and I am quite sure that the coolant that is used in 150 engines is more cerise than the redish of earlier models so maybe that has changed in production too.

A head gasket is a fairly inert thing once it is clamped up by the head so I doubt any change in compression from carbon could be significant enough to lead to failure

I agree. Increased compression would likely not cause it, but detonation can and one can lead to the other. For the potential effects of detonation on head gaskets in diesel engines see here:

http://www.enginebuildermag.com/Article/66704/uncovering_the_culprits_that_cause_head_gaskets_to_fail.aspx

As you likely know, the timing of the combustion in a diesel is dictated by the fuel injection, but will be influenced by the position of the EGR and the amount of compression amongst other things. The 2AD appears to have problems in both regards (i.e. it may think the EGR is shut tight and adjust the timing accordingly, but the valve is actually partially open, affecting the timing of the combustion and causing detonation). As an aside, according to Charlie's thread, the good will warranty covers: "2) Overheating & Head Gasket failure due to carbon deposits on the pistons", rather than "contamination".

[Devon Aygo]

Head gasket failure related to contamination on early engines was down to a reaction between the gasket material and the coolant in use at the time I believe.

Exactly - that was the explanation proffered at the time. They have since changed the head gasket material and I am quite sure that the coolant that is used in 150 engines is more cerise than the redish of earlier models so maybe that has changed in production too.

A head gasket is a fairly inert thing once it is clamped up by the head so I doubt any change in compression from carbon could be significant enough to lead to failure

There are two known issues that cause head gasket failure on the AD engines

1. Gasket failure due to faulty materials used in the gasket construction recognised and fixed by late 2007. Basically the coolant and head gasket suffered from a chemical reaction breaking down the gasket.

2 Gasket failure due to " Carbon stamping". Excessive amounts of carbon in the combustion chambers from engine oil burning as it had not been cleared from the bore due to poorly designed piston rings, allowed the carbon to slowly build up around the join between cylinder head and cylinder block, eventually the carbon starts to be " stamped" by the piston slowly pushing more and more carbon into the joint sealed by the head gasket. Ultimately causing the gasket to fail, this was recognised and fixed in early 2009

[anchorman]

Head gasket failure related to contamination on early engines was down to a reaction between the gasket material and the coolant in use at the time I believe.

Exactly - that was the explanation proffered at the time. They have since changed the head gasket material and I am quite sure that the coolant that is used in 150 engines is more cerise than the redish of earlier models so maybe that has changed in production too.

A head gasket is a fairly inert thing once it is clamped up by the head so I doubt any change in compression from carbon could be significant enough to lead to failure

There are two known issues that cause head gasket failure on the AD engines

1. Gasket failure due to faulty materials used in the gasket construction recognised and fixed by late 2007. Basically the coolant and head gasket suffered from a chemical reaction breaking down the gasket.

2 Gasket failure due to " Carbon stamping". Excessive amounts of carbon in the combustion chambers from engine oil burning as it had not been cleared from the bore due to poorly designed piston rings, allowed the carbon to slowly build up around the join between cylinder head and cylinder block, eventually the carbon starts to be " stamped" by the piston slowly pushing more and more carbon into the joint sealed by the head gasket. Ultimately causing the gasket to fail, this was recognised and fixed in early 2009

Thats the definitive explanation. Thanks DA.

[Dippy]

when hot. Soon after the start of production, the 4.3s received a series of changes which included new pistons, rings and other mods to improve the sealing internally and externally. These pretty much complete by mid to late 2008 and so engines produced from 2007 to the end of 2008 were effected to a deminishing amount to in many cases no measurable consumption. There may be odd exceptions.

Has anyone got a more detailed idea of what took place when, to allow owners, sorry workshops, to place a car more accurately along the line of development and understand what is likely to be inside? Either dates or engine number ranges?

I know that with Porsche such info was near impossible to get hold of, they were even saying the factory itself didn't know as the changes were phased in rather than introduced on a fixed date. But I ask the wise here anyway :)

[CharlieFarlie]

This has been asked before many times and of course the answers could and surely would never be found...

Imagine Toyota announcing engine numbers between this to that numbers are within the numbers they have assembled with bad rings or gaskets ..... There would be huge queues demanding replacement even if the cars are running perfectly...

So instead they brought about the current engine replacement scheme as a safety net.. I would bet Toyota do know the numbers though and cross reference them each time a claim is made ...

Sadly as we see often now owners finding themselves with failing engines that have passed the 7 year mark.. Will they feel or be happy ? Well unlikely but respect has to be given to Toyota for stepping in and offering the best viable solution .. No other manufacturer has ever extended a warranty by 4 years !!!

[kencat]

I bet Toyota know Exactly the engines ! As you say 7 year warranty very good ! Thank god I changed mine 2 a 150bhp ! It's the best car I've ever owned

[sonixtorm]

Head gasket failure related to contamination on early engines was down to a reaction between the gasket material and the coolant in use at the time I believe.

Exactly - that was the explanation proffered at the time. They have since changed the head gasket material and I am quite sure that the coolant that is used in 150 engines is more cerise than the redish of earlier models so maybe that has changed in production too.

A head gasket is a fairly inert thing once it is clamped up by the head so I doubt any change in compression from carbon could be significant enough to lead to failure

There are two known issues that cause head gasket failure on the AD engines

1. Gasket failure due to faulty materials used in the gasket construction recognised and fixed by late 2007. Basically the coolant and head gasket suffered from a chemical reaction breaking down the gasket.

2 Gasket failure due to " Carbon stamping". Excessive amounts of carbon in the combustion chambers from engine oil burning as it had not been cleared from the bore due to poorly designed piston rings, allowed the carbon to slowly build up around the join between cylinder head and cylinder block, eventually the carbon starts to be " stamped" by the piston slowly pushing more and more carbon into the joint sealed by the head gasket. Ultimately causing the gasket to fail, this was recognised and fixed in early 2009

Thanks for this; really interesting information.