GM Service Manual Online
For 1990-2009 cars only

Concern

Action

External oil leak

Inspect for any of the following conditions:

    • Plugged positive crankcase ventilation (PCV) orifice tube
    • Plugged or kinked PCV hoses
    • Damaged or incorrectly installed PCV hoses
    • Excessive crankcase pressure

Rough Idle

Inspect for any of the following conditions:

    • Plugged PCV orifice tube
    • Plugged or kinked PCV hoses
    • Leaking or damaged PCV hoses

Stalling or slow idle speed

Inspect for any of the following conditions:

    • Plugged PCV orifice tube
    • Plugged or kinked PCV hoses
    • Leaking or damaged PCV hoses

High idle speed

Inspect for a leaking or damaged PCV hose.

Sludge in the engine

Inspect for any of the following conditions:

    • Plugged PCV orifice tube
    • Plugged or kinked PCV hoses