TESTING

Inspect the PCV system hoses and connections at each tune-up and replace any deteriorated hoses. Check the PCV valve at every tune-up and replace it at 30,000 mile (48,000 km) intervals.

The PCV valve is easily checked with the engine running at normal idle speed (warmed up).

1. Remove the PCV valve from the valve cover or intake manifold, but leave it connected to its hose.
2. Start the engine.

   Fig. 1:Blow air from the cylinder head side of the PCV valve, it should flow easily

3. Place your thumb over the end of the valve to check for vacuum. If there is no vacuum, check for plugged hoses or ports. If these are open, the valve is faulty.
4. With the engine OFF, remove the valve completely. Shake it end-to-end, listening for the rattle of the needle inside the valve. If no rattle is heard, the needle is jammed (probably due to oil sludge) and the valve should be replaced.

   Fig. 2:Blow air from the air manifold side, check that the air passes with difficulty

   CAUTION
   Don't blow directly into the valve; petroleum deposits within the valve can be harmful.

   An engine without crankcase ventilation is quickly damaged. It is important to check the PCV at regular intervals. When replacing a PCV valve you must use the correct one for the engine. Many valves look alike on the outside, but have different mechanical values. Putting the incorrect valve on a vehicle can cause a great deal of driveability problems.

   Fig. 3:Leaks from any of these areas can cause the PCV system to malfunction