Engine Service Require - ECM6805

[RobI]

Read a lot of posts about the Engine Service Required as my car has been doing this for a few months now.
S60 2004 D5.

Took it to volvo carage at Bedhampton and they read of the fault code 'ECM 6805, BOOST PRESSURE CONTROL FAULT'. Report says they checked for air leaks, engine mounts and VNR solenoid, all OK. They blocked off the engine mount and asked me to try. Apparantly this is regulated by the turbo although I don't quite understand. Anyway, I tried the car for a month/ about 600 miles and it didn't return.
Now the car has the mount unblocked so it is part of the 'circuit' again and I can pretty much get it to get the fault every month or so. It could be that it is still intermittent and even when the mount was blocked for a month I could have jus been lukcy/unlcuky depending which way you look at it.

When I took it back to Volvo, they said it is rarely the mount even though this is the ting they asked me to try. They listed, pipers, mount, turbo govenor or the turbo as candidates which can introduce this falt code. Is there anything else?

I must say, the fault seems to reoccur when mid to hard acceleration with high gear/ low revs so I guess the pressure is building quite hard.

So the question is what is the way forward?

I'm loathed to replace part after part if it cannot be established what the fault is as this could get expensive. How much would a:

mount
inlet pipe
govenor
turbo

cost to replace (approx each)? Just so I can think about what is in store.

It bothers me that the garage said they didn't really know how the system works with the engine mount. They claim they inspected the pipes and mounts but who knows. I'm thinking about replacing the mount and the inlet as first step. I take it from them that they see it as my problem to just keep replacing parts until it is fixed, that sucks!

Fault goes away after engine off/ on again.

Any help greatly appreciated.

[Clan]

The engine mounts are made stiff or soft by vacuum , if they leak they will affect the turbo control which is also controlled by vacuum ... It is easy to test them by using a vacuum pump which the garage should have , if the vacuum holds then they will be ok ... you can try blanking them off again ...
The next stage would be a new Turbo control vacuum valve ... ( £50 , use a V50 2.0 D bracket kit which contains a turbo control valve ) Finaly if all else fails it is the calibration of the turbocharger internaly , perhaps a cracked variable valve ring ....
most cases of ECM 6805 are cured by changing the turbo valve , one or two have needed a turbocharger ..

[RobI]

Thanks for the reply.

Forgive my ignorance, is the Tubo control vacuum valve anything to do with the govenor (perhaps there are few names for these bits)? It's just that Volvo didn't mention this as a candidate that could be a problem (although they didn't seem too sure as you can see).

Just another bit more info on the fault, as mentioned it occurs with acceleration say in 2nd/3rd when revs are 1-2000 rpm. So it is like when the engine is a little bit bogged down in the rev range and I keep the accelerator reasonable hard until well, it fails and goes into limp mode (or I get lots of speed ;-)). I don't think I've ever managed to get this to occur when in the higher rev limit > 2500 with lots of boost/ speed (but I do drive like an old man I suppose).
Not sure if that extra bit of info helps.

So plan is looking:

- Get garage to vacuum test the engine mount.
- Replace turbo control valve. (Govenor?)

Worth replacing the inlet pipe? Car has done 80000 miles so I guess these things don't last forever.

Thanks again!

[GSMGuy]

Originally Posted by Clan

The engine mounts are made stiff or soft by vacuum , if they leak they will affect the turbo control which is also controlled by vacuum ... It is easy to test them by using a vacuum pump which the garage should have , if the vacuum holds then they will be ok ... you can try blanking them off again ...
The next stage would be a new Turbo control vacuum valve ... ( £50 , use a V50 2.0 D bracket kit which contains a turbo control valve ) Finaly if all else fails it is the calibration of the turbocharger internaly , perhaps a cracked variable valve ring ....
most cases of ECM 6805 are cured by changing the turbo valve , one or two have needed a turbocharger ..

Clan - You got a part number for this??

Mike

[Rubber]

Hi RobI,
i just found your thread, i have had the same thing happen to my v70 d5, under the same sort of conditions that you have to get the fault (low revs 2nd/3rd...foot to the boards) Only while the message "engine service required" was showing, i had no power, the car would rev to about 2500rpm and that was it! I stopped, switched engine off, then restarted, and all is fine.
Do you get the same loss of power?

Jon

[Clan]

Originally Posted by GSMGuy

Clan - You got a part number for this??

Mike

i'll find out tuesday ..

[grass hopper]

could be a induction leak,worth checking the intercooler for leaks,might also have signs of oil mist at the bottom.have seen a few that have also bowed out at the bottom,if its leaking and the boost flow does not correspond to the MAF reading it will go into limp home mode.

[RobI]

Hi All,

I have had the turbo governor replaced just over 2 weeks ago. So far looking ok.
Volvo said that if it was the engine mount then it would most likely show up as a problem more frequently because they are pressurised at startup. They said in their experience the engine mount has never cured this kind of problem (but clearly this is still something that needs to be considered).
They said they pressurised the system and held it to check for leaks, as none were found they ruled out leaks.
The next step was to replace the governor part number (30637251). Cost £114 +vat.
If this doesn't cure it then they were pretty sure the culprit would be the turbo (!!!). If that were the case I think I'd seek an 2nd opinion to be sure and also consider a recon turbo as I suspect a new one from Volvo would cost lots!

I'll post as soon as it goes wrong or even better :-) in some weeks time if it is all going OK (please god).

Cheers,
Rob

[RobI]

Just to confirm, yes, when the Engine Service Required light appears the engine is in limp mode for this fault so engine is limited to 2500rpm. Engine off/ on and fault is cleared so can then use all revs until next occurrence.

On my car the fault was latched in the computer memory so it could be read off by the garage. Not sure if the latching of the error has occurred for other sufferers of this problem. Hopefully this has helped in my case as it has narrowed down the search for the problem...

[Clan]

Originally Posted by RobI

Hi All,

I have had the turbo governor replaced just over 2 weeks ago. So far looking ok.
Volvo said that if it was the engine mount then it would most likely show up as a problem more frequently because they are pressurised at startup. They said in their experience the engine mount has never cured this kind of problem (but clearly this is still something that needs to be considered).
They said they pressurised the system and held it to check for leaks, as none were found they ruled out leaks.
The next step was to replace the governor part number (30637251). Cost £114 +vat.
If this doesn't cure it then they were pretty sure the culprit would be the turbo (!!!). If that were the case I think I'd seek an 2nd opinion to be sure and also consider a recon turbo as I suspect a new one from Volvo would cost lots!

I'll post as soon as it goes wrong or even better :-) in some weeks time if it is all going OK (please god).

Cheers,
Rob

If you do get the problem back now after having a new turbo control valve and sure there are no leaks from boost pipes or intercooler or engine mounts then the answer is a new turbo , dont waste money on reconditioning , there is likely to be nothing wrong with the main turbo components, the code indicates air flow calibration the calibration of the turbo conrol rod on the turbo is crucial .
you would have nothing to loose by trying an adjustment of the rod say one turn back then if that doesnt help two turns forward from there before you do go for the new turbocharger .. The problem sometimes is a sticking or cracked vane ring inside the turbocharger .