hi,
I have a S80 volvo, and when ever I am in traffic and temperature needle goes just abit over 50%, a whistling noise comes (like some high pitch vacuum/suction noise), it will go away when the car is moving and temperature needle comes back to 50% or lower.

If I am stuck in traffic and the engine is getting hotter, the noise stays, and some time the car will loose idling and my switch off.
sometime I even get low oil warning or a message saying no oil.

The Oil is there as I check regularly, i am definate its some sort of suction/vacuum noise only happens at high temperature.

any insight to my issue will be much appreciated, thanks in advance

 

Next time it happens if you can pull over open the hood and open the oil cap quick with it running if the noise goes away with the oil filler cap off the ventbox is bad.

 

Not sure what you mean by "ventbox". Are you referring to bad crankcase recirculating equipment?
My 1999 S80 non-turbo has a whistling engine compartment sound at 2000-2500 RPM under acceleration but not in neutral with my head under the hood. Should I just turn up the radio??
Thanks.

 

By vent box Yes I mean Engine vent system parts.
I would have it looked at it could be many things.

 

A bad oiltrap box will not cause the low oil light tho. May have more than one problem. There is a service bulletin out to replace the PCV nipples on the bottom of the intakes. that can cause this noise you descibe. and also you may have some engine cavitation. meaning air is getting into the oil from the o-rings in the oilpan pickup tube. that can cause the low oil light to come on..