Engine: D52447: Over Boost

[Shadeyman]

Driving home yesterday I put my foot down to catch up with faster moving traffic and noticed my boost gauge hit 22psi(never done that before), the car hesitated a little just as I was backed off the throttle.

Again this morning I put my foot down hard and the gauge read 29psi, but this time the "ENGINE SERVICE REQUIRED" popped up on the display.

The cars obviously over boosting for some reason, I'm guessing the vanes in the turbo are sticking causing it to over boost.
Its happened 3 times in two days. Anyone got any other idea's and how I can cure it ?

EDIT.

Got my VIDA/DICE hooked up to the car, read the fault code.

ECM-6805 Boost pressure control. Faulty flow

"Faulty Flow" ? Is this the MAF Sensor detecting more air flow than there show be ?

[Just Drive]

Not too long ago now I had a 2.0TDCI with same fault which was due to sticking guide vanes. Other than replacing turbo the manufacturer recommended procedure was to slowly build up the engine to high revs (>4000rpm) and stay like this for at least 45mins whilst driving on a motorway. This way the turbo would become so hot it would burn off any carbon deposits and free up the vanes.

I can't help but think this wouldn't have done the engine any good but it did sort the problem out and no more boost problems.

[JohnL]

The MAF doesn't detect the boost pressure there is sensor on the r/h side of the intercooler that measures the boost pressure.
Normal boost pressure should be about 2 bars.
What year is your car? Could be the inlet manifold deflector rod broken.
John

[dilksie]

There's a new product called Diesel Turbo Cleaner advertised in this months Car Mechanics magazine. Claims to clean your variable vane turbo and comes with a money back guarentee. Costs £49.99 and their website is www.automotivebrands.co.uk

[JohnL]

I have used a different product called Cataclean, did the job, and a lot less price.
John

[Shadeyman]

Originally Posted by Just Drive

Not too long ago now I had a 2.0TDCI with same fault which was due to sticking guide vanes. Other than replacing turbo the manufacturer recommended procedure was to slowly build up the engine to high revs (>4000rpm) and stay like this for at least 45mins whilst driving on a motorway. This way the turbo would become so hot it would burn off any carbon deposits and free up the vanes.

I can't help but think this wouldn't have done the engine any good but it did sort the problem out and no more boost problems.

I'll give it a try Sunday ...

Originally Posted by JohnL

The MAF doesn't detect the boost pressure there is sensor on the r/h side of the intercooler that measures the boost pressure.
Normal boost pressure should be about 2 bars.
What year is your car? Could be the inlet manifold deflector rod broken.
John

I said "air flow" not "boost pressure". MAF measures air flow, MAP measures boost. The cars a 2004 so I don't think there's a rod .. Cheers anyway.

Originally Posted by dilksie

There's a new product called Diesel Turbo Cleaner advertised in this months Car Mechanics magazine. Claims to clean your variable vane turbo and comes with a money back guarentee. Costs £49.99 and their website is www.automotivebrands.co.uk

Might give it a try if Just Drive idea fails.

[Shadeyman]

Used the car to pop and see my mom first thing this morning and on the way back home it lost power "ENGINE SERVICE REQUIRED" popped up again, same error code as before so I didn't bother taking it for a thrash on the motorway.

Instead I left the engine running, ran into the house and fetch my VIDA/DICE and plugged it into the car. Not really sure what I was looking for so I selected a few things to monitor and took it for a short drive, this was the result.



Now I'm no expert but as you can see from the graph the third time I put my foot down(between the red arrows) the "ENGINE SERVICE REQUIRED" disapeared and the car took off like a rocket. The main difference was the EGR activated. Could this "Faulty Flow" be due to the EGR, sticking etc. ?

[Shadeyman]

90 mile round trip this morning up and back down the M54.

Tried Just Drive's idea, no joy.

After reading numerous threads on here including the an awesome thread started buy Outnumbered(Mike) I'm 99% sure the vanes in the turbo are sticking at low vacuum levels due to a build up of soot/carbon.

How difficult is it to remove and clean the turbo, is it something I could do myself ?

[outnumbered]

you can do it yourself but its getting the turbo out on yours with the prop shaft, a bit more fidily there is a how to i think on the forum.
what i would do first is .
is yours manual.
if so 4th gear at 30mph and press the throttle to the floor for about 4 seconds what this achieves is the veins will be at the widest point untill it catches up try this few times to see if it works.
if not then off it comes.
mike

[Shadeyman]

Originally Posted by outnumbered

you can do it yourself but its getting the turbo out on yours with the prop shaft, a bit more fidily there is a how to i think on the forum.
what i would do first is .
is yours manual.
if so 4th gear at 30mph and press the throttle to the floor for about 4 seconds what this achieves is the veins will be at the widest point untill it catches up try this few times to see if it works.
if not then off it comes.
mike

Its an auto Mike. I did try slipping the gear nob over to the left and selecting 4th then flooring it but out of the 5 times I tried I was only able to do it 3 times as it lost power(engine service required) the other 2 times.

I've not had a close look at the turbo yet but from what I read in your thread I'm 99.9% sure that the problem is sticky turbo vanes.

Got to come off for that, not sure I'm up to the challange.

Where would I find this "How too" ?