2002 S80 2.9 engine whistle

thpavolvo · Post by **thpavolvo** » 24 Apr 2009, 11:36

Help: My 2002 S80 2.9 150K miles is whistling, and trying to suck air thru the oil fill cap and dipstick. As soon as I open the filler cap or dip stick I here a loud sucking sound like a vaccume being broken and the whistling stops. Any sugestions as to why and how to fix it? Thank you.

Post by **vegasjetskier** » 24 Apr 2009, 15:06

Sounds like you've got intake manifold vacuum applied to the crankcase. My guess would be the PCV system is messed up. I'm not sure if your car has a PCV valve on it or not, but if it does that is probably the culprit - stuck in the open position and constantly appying vacuum to the crankcase.

Post by **MadeInJapan** » 24 Apr 2009, 21:37

Certainly I would rather have vacuum than positive pressure. Maybe all that is wrong is that gaskets are bad. Replace the 0-rings on the dipstick and rubber gasket on the under side of the oil fill cap and see if it goes away.