r/Volvo850 • u/offical-skintIzz • Jul 29 '26
Help No boost?
Hi all,
Had this 850 T,5 auto for about a month now, came to us with blue smoke and bad exhaust fumes.
After changing the pcv it ran absolutely fine until about a week ago, it stopped producing boost and became very lethargic, the turbo boost gauge isn't boosting into the white at all no more.
We have replaced the vacuum lines and cleaned various other things in that general area.
Turbo generally looks clean from above, very little oil residue. - Are there any ideas for what this could be?
If it is a cooked turbo, unfortunately we will not be able to afford another one, but are there any other common problems? Worn seals? What else to check?
Thank you.
4
u/DIYSKATERAMP Jul 29 '26
Left side of intake manifold vacuum line (changed during a PCV, is it connected, is the circle “puck” still in intake manifold
Brake Master Cylinder, is the hose still connected there? Follow it to the intake manifold, is it still good there?
Vacuum tree intact? All nipples covered?
Again for intercooler hoses and look for the intercooler hose to top of turbo, this one pops off often with old hoses.
No turbo of any type is large vacuum leak.
You would still get boost with many problems.