The breather box is whistling and the vacuum pressure is so great I have a tough time getting the oil cap off. It will stop whistling when I either remove dipstick or oil cap.

On my old 740 usually PCV problems manifested with outward pressure pushing the dipstick out or oil from cap. This is reversed.

Realize the breather box is under the intake mainfold great place (shoot the engineer for this masterpiece). And the intake manifold needs to be removed to service this simple part.

I have searched everywhere and the 2003 setup for the PVC seems different then the earlier v70 and s70 models.

I trace the hose to the breather box from the hose near the oil cap but can't see where it connects to the air intake.

Can anyone give me insight on this and possibly other causes that may not require removing the intake mainfold.


Thanks Greatly

 

The vent box itself needs to be replaced. There is a diaphram built into the vent box that goes bad causing the issue.