GM Service Manual Online
For 1990-2009 cars only

Concern

Action

DEFINITION: During normal operation the crankcase gases can be seen exiting from the hose at the oil separator.

The maximum crankcase pressure is 4 kPa or 16 in of water at 3,100 RPM measured at the oil level indicator tube.

Oil leak - external

    • Plugged or kinked crankcase ventilation system hoses
    • Damaged or loose crankcase ventilation system hoses
    • Valve rocker arm diaphragm covers loose
    • Oil separator oil drain hose damaged or loose
    • Too much crankcase pressure

Odors

Normal situation

Noise

Cracked hoses

Smoke

Internal engine failure