GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2003 🢒 DeVille 🢒 Engine 🢒 Engine Controls - 4.6L 🢒 Crankcase Ventilation System Inspection/Diagnosis

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 hoses.

Sludge in the engine

Inspect for any of the following conditions:

    • Plugged PCV orifice tube.
    • Plugged or kinked PCV hoses.