See Figures 1, 2, 3, 4 and 5
The PCV valve system vents crankcase gases into the engine air intake where they are burned with the fuel and air mixture. The PCV valve system keeps pollutants from being released into the atmosphere, and also helps to keep the engine oil clean, by ridding the crankcase of moisture and corrosive fumes. The PCV valve system consists of the PCV valve, its mounting grommet, the nipple in the air intake and the connecting hoses. On some engine applications, the PCV valve system is connected with the evaporative emission system.
The PCV valve controls the amount of vapors pulled into the intake manifold from the crankcase and acts as a check valve by preventing air flow from entering the crankcase in the opposite direction. The PCV valve also prevents combustion backfiring from entering the crankcase in order to prevent detonation of the accumulated crankcase gases.
See Figure 5
- Remove the PCV valve from the valve cover grommet.
Shake the PCV valve.
- If the valve rattles when shaken, reinstall it and proceed to Step 3.
- If the valve does not rattle, it is sticking and must be replaced.
- Start the engine and allow it to reach normal operating temperature.
Check the PCV valve for vacuum by placing your finger over the end of the valve.
- If vacuum exists, proceed to Step 5.
- If vacuum does not exist, check for loose hose connections, vacuum leaks or blockage. Correct as necessary.
- Disconnect the fresh air intake hose from the air inlet tube (connects the air cleaner housing to the throttle body).
Place a stiff piece of paper over the hose end and wait 1 minute.
- If vacuum holds the paper in place, the system is OK; reconnect the hose.
- If the paper is not held in place, check for loose hose connections, vacuum leaks or blockage. Correct as necessary.
REMOVAL & INSTALLATION
- Disconnect the vacuum hose from the PCV valve.
- Remove the PCV valve from its mounting grommet.
- To install, attach the PCV vacuum hose to the PCV valve, then insert the valve into its mounting grommet.