Functional Check

If engine is idling rough, check for a clogged PCV system. Check for leaks in the PCV system. Replace as required.

Use the following procedures to determine if the PCV system is functioning properly:
1. Remove PCV vent from cam vent housing.
2. Run engine at idle.
3. Place your thumb over end of vent housing hose to check for strong vacuum signal. If there is no vacuum present, check for a plugged intake manifold port. Replace any clogged components or clean out plugged port.