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Positive Crankcase Ventilation System

  1. Stuck PCV Valve Check -  Turn ignition off. Verify PCV valve maintenance schedule has been performed. Remove PCV valve. Verify PCV valve is correct part number. Verify PCV valve is clean. Shake PCV valve. If PCV valve rattles when shaken, reinstall PCV valve. Go to next step. If PCV valve does not rattle when shaken, PCV valve is sticking. Replace faulty PCV valve.
  2. PCV System Check -  Start engine and idle until normal operating temperature is reached. Disconnect closure (fresh air) hose from remote air cleaner or air inlet tube (tube connecting mass air flow sensor and throttle body). Put a stiff piece of paper over hose end and observe. Wait one minute. If vacuum holds paper in place, PCV system is okay. Reconnect hose. See SYMPTOM DIAGNOSIS in TROUBLE SHOOTING - NO CODES article. If vacuum does not hold paper in place, PCV system is leaking, plugged or EVAP system is leaking. Go to next step.
  3. EVAP Emission System Check -  If EVAP emission hose is not connected to PCV hose, perform no further action. Otherwise, disconnect EVAP emission hose at PCV hose connection (if equipped). Cap connector. Again, place a stiff piece of paper over closure (fresh air) hose end. Wait one minute. If vacuum holds paper in place, PCV system is okay. Go to  4 under DTC P0455 OR DTC P1443. If vacuum does not hold paper in place, check for vacuum leaks or obstruction in PCV system. Check oil cap, PCV valve, hoses, grommets, valve cover bolt torque and/or gasket leak. Repair as necessary.
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