ECM 6805 boost returning through air intake

[Bigdave0785]

Hi all, I hope you are able to spare me 5 minutes as I’m at the end of my tether. I have the ecm6805 fault code boost pressure faulty flow. I have been through the whole vacuum system and everything seems as it should, I replaced the turbo control valve, (I think that’s what it’s called, the one bolted to the front of the engine that supplies the actuator) what the car is doing, when I rev it, from high revs to idle it seems to be throwing boost back up the air intake, a whooshing sound like a dump valve/anti lag kind of noise. Iv stripped the egr and cleaned it out, it wasn’t too bad to be fair. I’m wondering if it could be the vanes sticking and was wondering if that’s what it could be before I start unbolting the turbo as it looks tricky to get to all the bolts. I have applied vacuum to the actuator and the arm moves about 1 cm but it’s hard to move manually. Any help would be most appreciated as iv spent days on it now with no success. Many thanks

[gmonag]

I think you have aswered your own question. I asssume you have a 163hp. If you have eliminated vacuum system faults then I would bet that your turbo inlet guide vanes are gummed up (the sticky actuator confirms this). I've been through this personally, same symptoms. You might get some temporary improvement by performing an in-place clean of the turbo vanes (Mr Muscle) but it will not be a permanent fix. Change the turbo.

An exchange refurbished turbo is about £300. Removal and fitment is a bit tricky (the turbo usually will not come out of the top).

[Bigdave0785]

Just as I suspected, will strip it down and have a look, thanks for the reply

[Bigdave0785]

Struggling to get the bolts out, are these additives that supposedly clean the turbo out any good or are they a waste of time

[gmonag]

You may get some temporary improvement. I tried Revive and Mr Muscle. They may work if the vanes are not too far gone but I suspect that yours, like mine, are coked up too badly.

[osullivant]

Originally Posted by Bigdave0785

Struggling to get the bolts out, are these additives that supposedly clean the turbo out any good or are they a waste of time

If you shear off the bolts you are F>>>>d. and it becomes a nightmare.

Try the mr muscle and anything else that might possibly give you a better indication that it is the vanes before pulling the turbo,

I had ferocious job with rounded and sheared bolts in mine and subsequently bought a turbo from a scrap yard all bolts sheared in that also...

I eventually spent the bobs and bought a span new turbo, this was not cheap... (mine is the 185 and slightly harder to get out the angle gear but I think it still needs to come out to get the turbo off in the 163...)

[Bigdave0785]

Originally Posted by osullivant

If you shear off the bolts you are F>>>>d. and it becomes a nightmare.

Try the mr muscle and anything else that might possibly give you a better indication that it is the vanes before pulling the turbo,

I had ferocious job with rounded and sheared bolts in mine and subsequently bought a turbo from a scrap yard all bolts sheared in that also...

I eventually spent the bobs and bought a span new turbo, this was not cheap... (mine is the 185 and slightly harder to get out the angle gear but I think it still needs to come out to get the turbo off in the 163...)

What do you do with the mr muscle to clean turbo out, I don’t suppose you spray it in the intake

[gmonag]

https://www.volvoforums.org.uk/showt...ghlight=muscle

[Bigdave0785]

Originally Posted by gmonag

https://www.volvoforums.org.uk/showt...ghlight=muscle

Awesome Greg, will give it a try, thank you very much. Just out of curiosity, is it just the Mr Muscle oven cleaner

[gmonag]

Yes. Wear gloves and eye protection.

NB it will only be a temporary fix.