2002 Mercury Villager BaseFACTORY OEM SERVICE PROCEDURE

Test Hg: Positive Crankcase Ventilation System: Testing

  1. 1) Check PCV System

    Start engine and warm to normal operating temperature. Disconnect hose from PCV valve. Listen for hissing noise from PCV valve. Place a finger over valve, strong vacuum should be felt. If vacuum is strong, go to next step. If vacuum from valve is weak, replace PCV valve and recheck for vacuum.
    2. NOTE: If air pressure, oil, or oily sludge is present at intake end of fresh air supply hose, engine has excessive blow-by. Possible cause is cylinder bore, piston ring, or valve stem wear. Diagnose engine blow-by. See appropriate article in ENGINES.

  2. 2) Check System Hoses
    Remove all PCV system hoses. Check for evidence of excessive blow-by (oily sludge) at intake end of fresh air supply hose. Check all hoses for leaks, loose connections or blockage. Repair as necessary. If hoses are okay and excessive blow-by is not present, return to symptom that directed you here. See SYMPTOM DIAGNOSIS under SYMPTOMS in TROUBLE SHOOTING - NO CODES - VILLAGER article.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.