Contents: Description ⇊ Examination ⇊
Description
The positive crankcase ventilation (PCV) system prevents crankcase gases from escaping into the atmosphere. The PCV valve has a spring-loaded plunger. When the engine is started, the plunger in the PCV valve rises proportionally to the vacuum in the intake manifold and crankcase gases are sucked directly into the intake manifold.
1. breather tube; 2. intake manifold; 3. pcv hose; 4. pcv valve; black arrow: crankcase gases white arrow: fresh air
Examination
1. Check PCV hoses and fittings for leaks or blockages.
1. breather hose; 2. PCV hose; 3. PCV valve
2. Make sure that at idle speed, when you lightly squeeze the hose between the PCV valve and the intake manifold with your fingers or pliers, a clicking sound is heard from the PCV valve.
If there is no clicking sound, check the PCV valve rubber bushing for cracks or damage. If the bushing is OK, replace the PCV valve and recheck.