S80 D5 Clogged PCV(/crankcase breather)?
 

Hello all.

Im again having some problems with my somewhat recently purchased S80 D5 (2002).
The car went into limp mode a couple of days ago and wont come out of it.
Well, it throws me into limp pretty much as soon as the turbo kicks in. Sometimes it lets me accelerate to the end of 1st gear and then into limp.
Read the codes with vida and they showed: ECM-6805 Boost pressure control - faulty flow, and ECM-130A Mass air flow (MAF) sensor - faulty signal.

Funny thing is I changes the MAF in july and it hasn't given me this error up until now. (reading about it on VIDA it could just mean a vaccuum leak in the engine mounts).

I've also noticed the car likes to eat oil. Too much to be normal (about a liter every month). Some leaks i found under the bonnet were around the oil filler cap, and near the dipstick (further investigation also revealed that the intercooler has some damage near the bottom edge and there seems to be oil/sludge leaking from there as well). Further googeling leads me to believe this is because the PCV/crankcase breather valve/system is clogged.

Would this also explain the Boost Control valve faulty flow code? (my theory for that would be that the engine is forcing oil through the boost control system and clogging the valve.)

Now. I've looked and looked and looked and can't seem to find good source material on how to clean the PCV/crankcase breather system.

Could someone who has done this before enlighten me on this subject a little and maybe throw some parts numbers my way so i can look them up in the stores local to me?

Thanks in advance my dudes!

Hi The D5 Does not have a PCV System,
Dave

I must of mistaken PCV for crankcase ventilation. (Followed SiRobbs video on the volvo D5 oil filler popping noise and he mentioned a clogged PCV system, which got me researching that).
Sorry for embarrassing myself so bad :emoticon_U:

No problem ,
So you have vida,
look to see what the boost is going to before limp mode,
It sounds like it is over boosting,
when using vida, do a vnt actuator test and see if you can see it move smoothly ,
The vnt turbos are known to stick, because of carbon, if there was a leak on the engine mounts the car would not over boost,
have a look at the air pipe going to the cold side of the turbo, these do split
and then the car can over boost and the MAF will not be seeing the correct amount of air, so the MAF is may be fine,
to check the pipe remove it so you can have a good look,
also do change the intercooler as the leak will make the turbo work more to make the correct boost,
so this will be a problem as well,
Dave

Ill get that on the to-do list tomorrow.

How should i continue on the crank case breathers tho? Am i safe just taking the pipes and the oil trap/separator off and cleaning them? Anything i should look out for when handling these pieces?
Better safe then sorry :thinking:

oil trap/separator , I don't know I have never done it,
let me know how it goes,
Dave

Hi with it using a lot of oil,
remove the under tray and look to see if there is any oil leaking
from anywhere,
Dave

how many Miles has it done,
Dave

Theres a bit seeping from the back of the valve cover gasket but that seems to be the only place. Turbo looks mostly clean from underneath as well.

The car has done almost 250k miles but the last owner(s) have kept up with basic maintenance pretty well. Oil was changed 10k miles ago and belts/pulleys were done 40k miles ago. The engine mounts all look rather new but those dont seem to be documented.

Having a look at where the crankcase breather lines go and noticed that the "tub" they're connected to (near the boost control solenoid) is cast into one piece with the oil filter housing.
Afraid to dismantle that part for now because there does seem to be a lid and gaskets that im gonna have to replace when i remove them.

Wondering now if it would help to just remove the pipes from the "tub" and wash them out with brake clean?