The PCV system ensures that crankcase gases are led through a special valve through a hose back into the intake manifold, from where they enter the combustion chambers and are burned out during normal engine operation. The system consists of a hose running from the cylinder head cover to the intake manifold and a fresh air supply hose routed between the air cleaner and the cylinder head cover.
The PCV valve with a hose connected to it is seated in the intake manifold under the fuel line, or located at the rear of the engine, depending on the model (see illustrations below).
1. With the engine idling and warmed up to normal operating temperature, pull the valve and remove it, together with the connected hose, from the inlet pipe or hose.
2. Place your finger on the hole in the PCV valve or hose (see accompanying illustration) – a vacuum should be felt, otherwise make sure that the hose, the fitting on the inlet pipeline and the valve itself are passable. Replace defective components. 3. Stop the engine and shake the PCV valve - it should rattle slightly, otherwise replace it.
4. To replace the PCV valve, disconnect it from the vacuum hose, remembering the direction of connection.
5. When buying a new valve, make sure that it matches the size of your car engine. It would be best to directly compare the new valve with the old one removed from the engine.
6. Connect the replacement PCV valve to the vacuum hose, making sure they are securely connected.
7. Check the condition of the hoses and rubber bushings. Replace defective components.
8. Fit the valve firmly into place. For more information on the operation of the PCV system, see Chapter Engine management systems this guide.