Thumbs Up To Toyota!

[bomber06]

In October of last year the 3 dreaded warning messages appeared on the dashboard. It turned out to be a sticking EGR valve, and with anchoman's help the local dealership agreed to clean it free of charge!

Over the last week or so the RAV hasnt been running too well and I suspected that the EGR valve might be needing another clean out. This morning the 3 warning lights appeared. I took the car straight to my local dealers to see what they had to say. To my surprise they informed me that it wasnt the EGR, there was a problem with the catalytic converter with a cost of £1500 to replace. The RAV is over 4 years old and out of warranty so I thought I was going to have to dig deep to get it sorted

But, to the credit of the dealership they have negotiated with Toyota UK to change it free of charge!!!!!!!!!!!

Interestingly, the service guy said that the over fueling had most probably caused the cat problem, the same problem that causes the EGR to block. He said that they had changed a couple of cats recently and they would upgrading the software on the car to stop the over fueling. I did have a software reflash 2 years ago at service time, but this seems to be something new. Maybe they have come up with a software change that might cure the over fueling/EGR issue and at the sametime increasing the mpg a wee bit!?

Anyway I am just pleased to get it sorted free of charge, so here is a massive thumbs up to Minories Toyota Durham!

[anchorman]

Good info Bomber!

[Big Kev]

Bunnets aff to your dealer, Bomber, but what is "over-fuelling" when it's at home? If this covered in previous threads re EGR, tell me to go away and read them.....I won't take the garden gate....sorry....a fence.

Big Kev

[bomber06]

Not sure myself Big Kev.

I think Anchs has described how the EGR gets blocked in one of his posts, but i took as "over fueling" as a proportion of the fuel not being fully combusted i.e carbon deposits left within the fuel system.

Sorry i can't give a better definition.

[KPARRIS-JONES]

Nice one buddy, a massive save for the sake of a small bit of hassle!

[bothwell_buyer]

In my quest to attain supersonic speeds along the un-opened M74 (honest... they are still building it but theres bits of bridges missing so the RAV needs to learn how to fly)

I learnt that the engine management systems provided by Toyota aim to flood the engine if you attempt to over-rev it. The ecus desire to protect the engine seems to reach uncharted territory sometimes....but I found out. I took number 1 RAV to a 4x4 rolling road ( the road doesn't actually roll... its the car that sits on rollers and then they put the foot down/accelerate whilst the car sits in 3rd gear on the rollers) where they monitor the engine.. and I saw that the engine flooded at revs above about 5000.

However with a diesel, this threshold will be much lower...so... I wonder if the enforced threshold system actually destructs yer dieselly oil burning engine in the long term????

[bothwell_buyer]

a catlytic convertor thingy is worth a fortune in the scrap metals market

[local hero]

In October of last year the 3 dreaded warning messages appeared on the dashboard. It turned out to be a sticking EGR valve, and with anchoman's help the local dealership agreed to clean it free of charge!

Over the last week or so the RAV hasnt been running too well and I suspected that the EGR valve might be needing another clean out.

I am sorry but I really really do not get this EGR cleaning out thing, I am not mechanical in any way, but i have driven diesel trucks buses vans cranes + cars for forty years + why any diesel car should need this doing at 20,000 mls is beyond me, I have had EGRs cleaned + replaced but at 100,000mls plus, If it is normal for our Ravs then why is it not part of the service schedule, but more to the point WHY are they clogging up, there has to be a fundamental design or ecu fault causing this to happen + i do not believe the emissions c**p as all the cabs have had to pass the Euro 1V emissions test for at least the last 5yrs and are tested every 6 mths... Overfuelling to me means running too rich, I have mentioned this before and got little response but have you noticed how "sooty" our exhausts are compared with some other diesels I believe this is also a sign of overfuelling but WTF do I know.. Stew

[anchorman]

OK, I'm not sure petrol ECUs work anything like Euro IV diesel ones do but you are right about the cats bothy, there was a spate of them being sawn out from new 4X4s because they were easy to crawl under!

I would have loved an automatic this time around but I didn't because - a/ the 6 speed now is very acceptable (not perfect) and b/ I would have ended up with the D-CAT system. In the latter case this would have made enough difference in emissions to go from £155 VED to £425.

So what is this all about? You need to understand that the car has had 4 years to evolve and it would be premature to assume that the "problems" still exist in terms of reliability. Consider first the 2006 models. In its 136 powered version it was prone to burn oil. As with most diesels, an EGR valve (exhaust gas recirculation) was employed which balanced emissions by admitting varying amounts of exhaust back into the inlet. Since the engine is computer controlled it makes sense that the EGR should use an electric motor driven plunger so it can be metered accurately. If you uprate the power as in this case to 177, the emissions take a hammering so to offset those emissions the D-CAT system was employed (already this had been used by Lexus). In this version there was a "5th injector" which adds fuel to the exhaust by varying amounts to balance the emissions under certain loads. Also, a DPF (diesel particulate filter) was added to the exhaust to filter out any excess carbon and of course the obligatory EGR valve was retained. There is one other important consideration for both versions and that is the quality of fuel. There have been numerous trade journals that have demonstrated that high quality fuel not only cleans the internal engine parts but also keeps injectors free and in our own experimentation we have seen that the soot from low quality fuel is hard and crusty while that from high quality fuel is very soft and powdery.

Now put this all together. 136 versions were consuming oil and feeding that back through the EGR into the inlet for another go around. 177 versions were also feeding fuel into the exhaust so a cocktail of oil and excess fuel were adding to the carbon the DPF had to contend with over that of normal combustion and then we unsuspectedly made things worse by gluing it all together with supermarket weasel pee (by this time Lexus owners had been expressly forbidden from using it). Now you can see that early versions were prone to EGR problems on the 136 version and we were adding to the problems of the 177 with the fuel and causing the 5th injector to gum up and overfuel i.e. dribble neat fuel into the engine inlet instead of vaporising it and it all made its way to the DPF to clog it solid. Cars that are doing short trips and running rich while they warm up are even more prone to problems than those tonking up and down the motorway at speed and clearing the flue out! By May 2007 the oil consumption had been addressed and by about the same time the following year a new design of EGR less prone to sticking had been employed. For those running cars before that time you can make your life a lot easier by regular oil changes with good quality low viscosity oil like 5W/30 semi synthetic and premium fuel like Shell V-Power, BP Ultimate or Total Excellium. No doubt we will continue to read the exploits of the unsuspecting as they come to the forum for help.

To summarise, from launch to May 2007, 136 (XT3 to XT5 models) engines are very prone to EGR sticking, T180s from the same period are very prone to EGR, 5th injector and DPF clogging. In both cases this is exacerbated by using supermarket fuel and conversely the risk very much reduced by using high grade fuel.

From May 2007 the oil consumption is significantly reduced and those problems above also significantly reduced.

By the middle of 2008 a new EGR is introduced to production models and as a mod to problematic existing models virtually eliminates sticking and a new ECU flash (re-program) for all models from launch is brought in as a campaign and production. Any dealer will tell you if your car has been done and confirmation stickers are applied (unfortunately not all positioned in the same place).

Facelifted 2009 models get a virtually reworked 2.2 engine rated at 150. The cylinder block now has large internal breather holes to prevent pressurisation of the crank case and subsequent oil blow by (oil forced into the combustion chamber and burned), many modifications to the pistons, rings and other sealing weak spots, new cylinder head and gaskets and all models get piezo operated injectors. Oil consumption is eliminated, emissions reduced and fuel consumption improved. The EGR is changed to a gate type replacing previous plunger types.

The auto box has a similar effect in raising emissions and for those models the D-CAT system has to be retained albeit in a hugely modified form.

While the power of the T180 cant be compared with these newer engines, a test drive will definitely convert previous 136 engined owners it is so different.

Stewpot

I hope this goes some way to help you understand why there were problems mainly with earlier models. The old adage of kiss (keep it simple stupid) applied to many manufacturers EGR designs but they didnt proffer the amount of accuracy the RAV system was looking for and the high mileage of a taxi also improved reliability. Its like an old garden gate keep using it and the hinges will keep free but little use will cause it to sieze up!

[Big Kev]

Thirteen out of ten for explanation, Anchs, much as I still appreciate I will need to read anurra 4 times to fully take it all in. It was my intent to clean mine out in the near future, but since 7k of its 11k miles have been done on the expensive diesel, am I just doing it for doing its sake? No performance drop offs, no flat spots, no puffy smokey bits have been recorded, albeit I have two weeks planned in southern Englandshire mid August, so will rack up a good 1500 miles.

Regards,

Big Kev

[anchorman]

Thirteen out of ten for explanation, Anchs, much as I still appreciate I will need to read anurra 4 times to fully take it all in. It was my intent to clean mine out in the near future, but since 7k of its 11k miles have been done on the expensive diesel, am I just doing it for doing its sake? No performance drop offs, no flat spots, no puffy smokey bits have been recorded, albeit I have two weeks planned in southern Englandshire mid August, so will rack up a good 1500 miles.

Regards,

Big Kev

Yours is low risk with good fuel anyway. Don't be afraid to wind it up once in a while and don't panic if you see a cloud of grey smoke as it will self purge the DPF from time to time.

[Parts-King]

a catlytic convertor thingy is worth a fortune in the scrap metals market

We know to our cost as a dealership, pikeys steal them 10 at a time in night time raids from our compound

Kingo

[Plutus]

So, the auto diesel has an "improved" version of the "old" system whereas the current manuals have a completely new system?

Is this correct AM?

[anchorman]

So, the auto diesel has an "improved" version of the "old" system whereas the current manuals have a completely new system?

Is this correct AM?

No. The manual and auto versions both use the same 150 engine in terms of all the new mechanical features and in addition the auto gets the same type of gate EGR valve as the new manual. Although the auto has he same basic components of the D-CAT system as the old T/SR180 - 5th injector, EGR cooler, DPF and piezo injectors, they are all modified to improve the emissions and fuel consumption - and reliability! The 150s in both manual and auto forms are similar to the old 136/177 basic engines but with many improvements. I guess the way to describe it is a new engine designed from the weaknesses of the original.

[Plutus]

Thanks AM