Positive Crankcase Ventilation: Testing and Inspection

Crankcase Ventilation System Inspection/Diagnosis

1. Remove the positive crankcase ventilation (PCV) valve. Refer to Positive Crankcase Ventilation Valve Replacement (Service and Repair).




Warning: Refer to Fuel Vapors in Evaporative Emission Components Warning (Service Precautions).

2. Blow air into the cylinder head side of the PCV valve. Verify that air passes through the PCV valve easily.

• If air does not pass through the PCV valve, replace the PCV valve. Refer to Positive Crankcase Ventilation Valve Replacement (Service and Repair).




3. Blow air into the intake manifold side of the PCV valve.
4. Verify that air does not pass through the PCV valve easily.

• If air passes through the PCV valve, replace the PCV valve. Refer to Positive Crankcase Ventilation Valve Replacement (Service and Repair).

5. Inspect the PCV hose for damage, restrictions, or leaks. Replace the hose as necessary.
6. Inspect all PCV system passages and connections for leaks or restrictions. Repair as necessary.