Turbo Fault

[allegroequipe]

seems like a lot of people have this problem with the car going into limp mode, normally while overtaking, going up hill. The D4D- turbo is variable vane (trying to maximise google search to help others so excuse teaching to suck eggs!). The turbo gets coked up and the vanes stop moving so we need to get them moving again (or pay £2500 for a new turbo). Coke is hard but can be softened to allow the blades to move. A previous post said Halfords 10k boost worked, which it did on my car for the first 10K miles (what it sad on the tin) but then the turbo stuck again after 4k and £20 seemed a lot to pay every 4 months so... so I poured Wynnes diesel treatment straight in the turbo intake (like we used to do with redex into the carb!). I set the revs to 3000 first and after pouring the treatment into the turbo for 3 secs the revs rose to 4500 for 5 secs before reducing back to 3000. With a 3 sec pour and 20 sec wait it took about 10 mins to get the whole bottle in. I then drove 2 miles, left the car 1 hour and then moved the stepper unit pintle up an down about 10 times with my finger. This is hard to do on a Previa as it as at arms length. If you put a piece of card over your finger tip it doesn't hurt as much. If you remove the fuse box you can get both hands to the pintle to wiggle it and move the blades to free up the carbon. After 3 months of the car not going over 3000 revs it now revs to 5000 quite happily and all for £7!!! I'll post next time I get p1251 but not before. I normally drive 12k a year so if no posts before 12 months it has worked for 12k!!

[allegroequipe]

well, it wasn't the turbo this time after all.

I downloaded the workshop manual from 'ibid' for $5 and then tested the likely culprits. SCV's tested ok with an ohmmeter as did the PSV sensor. The air flow meter had no resistivity though indicating it was dead. Hopefully the one from eBay for £20 will cure the problem!

[jedi134]

I`m suprised the Turbo still works after all that stuff you`ve poured into it. Why not try a can of coke, its been known to be quit effective

[luke4x4tech]

pouring liquid into a moving " air steam" and flamable liquid into a diesel air intake ??? ,

Just to mention the carbon builds up in the rotor part of the vien control, exhaust side, so pouring stuff into intake won't do anything apart from feed the car with more fuel than it needs and possibly clogging up your diesel cat with a moist carbon exhaust gas thus reducing gas flow.

better to just move the control arm up and down and give it a good blast to clear it out ( not just reving the engine up on the drive )

[AaronDavid]

Where is the turbo?

[anchorman]

Where is the turbo?

Perhaps you should take it to a garage

[allegroequipe]

Hello chaps. I used the fuel treatment thinking it would be a cheaper version of Halfords 10k boost. It worked for about 50 miles then power dropped after 3000 revs again. I tested the Air mass meter, VSV sensor (Toyota workshop manual actually shows air flow through it back to front which really threw me - nearly replaced it!) and SCV's all ok.

Just removed and decoked the EGR. Wasn't much in it to be honest. Soaked it in brake cleaner for 10 mins, then blasted out with pressure washer. Plunger moves up and down easily now. Re-installed and she's fixed. Flies upto to 5000 revs again in all gears (we'll, not tried 5th at that speed!).

Reckon the fuel treatment and/or 10k boost released the valve temporarily by softening the carbon but not enough to stay fixed.

Pleased with a nice easy (less than 60mins) fix!

[Bodgit-fixit-run]

Anyone got any assembly diagrams and clearance details please. have gone through evrything else still getting the fault code when towing. Now getting a funny noise from it when turning off the engine. i think a bearing has gone. it needs to come out and be sorted. Oh well keeps me out of trouble.