engine crankcase on 2003 Volvo S80

when engine warm (to temp) stats to whistle,,remove oil cap, subsides,,crankcase some what plugged ??what do i do.

Asked by for the 2003 Volvo S80
1 answer
This may be a leaking crankcase hose under the intake manifold. I've seen it a few times on the XC90's. This repair is quite difficult, so I advise you take it to an experienced Volvo shop to address this.