Crankcase Ventilation System Inspection/Diagnosis
WARNING: This page is about a different car, the 2003 Pontiac Aztek and 2003 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
- Disconnect the PCV hose.
- Start the engine.
- Check for vacuum at the hose. If there is no vacuum, check for a plugged hose or manifold port. Check for a hose that collapses when blocked (vacuum applied). Replace the plugged or the deteriorated hoses.
- Allow the engine to idle at normal operating temperature.
- Remove the engine oil dipstick and install a vacuum gage on the dipstick tube.
- Block off the PCV system fresh air intake passage.
- Run the engine at 1500 RPM for 30 seconds, then read vacuum gage while engine is running at 1500 RPM.
- If vacuum is present, this indicates that the crankcase ventilation system is functioning properly.
- If no vacuum is indicated, the engine may not be sealed and is drawing in outside air.
Check the valve covers, the oil pan gasket or other sealing areas for leaks.
- If the vacuum gage registers a pressure, or if a vacuum gage is pushed out of dipstick tube, check for a plugged PCV port, a plugged hose or an excessive engine blow-by.