HG: Positive Crankcase Ventilation (PCV) System

HG: Introduction See: HG: Positive Crankcase Ventilation (PCV) System - Introduction

HG1 STUCK PCV VALVE CHECK

• Verify PCV valve maintenance schedule has been followed.
• Verify proper PCV valve part number.
• Verify clean PCV valve.
• Shake the PCV valve.

Does PCV valve rattle when shaken?
Yes

• REINSTALL PCV valve. GO to HG2

.

No

• PCV valve is sticking.
• REPLACE PCV valve. VERIFY a symptom no longer exists.

HG2 PCV SYSTEM CHECK

• Start engine and bring to normal operating temperature.
• Disconnect closure (fresh air) hose from remote air cleaner or air outlet tube (tube connecting mass air flow sensor and throttle body).
• Place a stiff piece of paper over the hose end. Wait one minute.

Does vacuum hold the paper in place?
Yes

• PCV System is OK. RETURN to Section 3 See: Symptom Related Diagnostic Procedures for other possible

causes of vehicle symptoms.

No

• System is leaking/plugged or Evaporative Emission System is

leaking. GO to HG3
.

HG3 EVAPORATIVE EMISSION SYSTEM CHECK

Note: If the evaporative emission hose is not connected to the PCV hose, follow the No Action to Take (refer to VECI decal).

• Disconnect evaporative emission hose at connection to PCV hose (if equipped). Cap the connector.
• Again place a stiff piece of paper over the closure (fresh air) hose end, as inHG2 . Wait one minute.

Does vacuum now hold the paper in place?
Yes

• PCV system is OK. REFER to Evaporative Emissions System.

No

• CHECK for vacuum leaks/obstruction in the PCV system (such as

oil cap, PCV valve, hoses, cut grommets, valve cover bolt torque/gasket leak).
REPAIR as necessary.