Test Procedure
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- HG1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS)
- Carry out the PCM self-test.
- Check for DTCs P053A, P0093, P0094, P1121, P145E, P1489, P2279, P2280, P2281 or P2282.
Are any of the above listed DTCs present?
Yes No For DTCs P053A, P145E and P1489, GO to HG5. For all other symptoms without DTCs, GO to HG2. - HG2 VISUAL INSPECTION OF THE PCV VALVE
- Remove and inspect the PCV valve for damage.
- Check the PCV valve, hoses and connections for leaks or restrictions.
- Verify the PCV valve maintenance schedule has been followed.
- Verify the correct PCV valve part number.
- Verify the PCV valve is clean.
- Verify the fresh air tube and related hoses are clean and routed correctly.
Is a concern present?
Yes No REPAIR as necessary. VERIFY the symptom no longer exists. GO to HG3. - HG3 STUCK PCV VALVE CHECK
- Disconnect the PCV valve from the valve cover.
- Shake the PCV valve.
Does the PCV valve rattle when shaken?
Yes No REINSTALL the PCV valve.
For PCV systems with electrical heating, GO to HG5.
For PCV systems without electrical heating, GO to HG10.The PCV valve is sticking. INSTALL a new PCV valve. VERIFY the symptom no longer exists. - HG4 CHECK FOR VACUUM LEAKS
- Check for a damaged or disconnected PCV vacuum hose.
- Check for air leaks between the throttle body and intake valves.
- Visually inspect the intake throttle plate for sticking or binding.
- Verify the correct PCV valve part number.
Is a concern present?
Yes No REPAIR as necessary.
Clear the PCM DTCs. REPEAT the self-test.GO to HG11. - HG5 CHECK THE HARNESS VOLTAGE TO THE PCM CONTROLLED PCV HEATER
- Suspect PCV connector disconnected.
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) PCV Connector, Harness Side (-) IGN START/RUN - Pin 2 Ground
Is the voltage greater than 10 V?
Yes No GO to HG6. REPAIR the open circuit. Clear the PCM DTCs.
REPEAT the self-test. - HG6 CHECK THE HARNESS CIRCUIT TO THE PCM CONTROLLED PCV HEATER
- Ignition OFF.
- PCM connector disconnected.
- Measure the resistance between:
(+) PCM Connector, Harness Side (-) PCV Connector, Harness Side PCVHC PCVHC - Pin 1
Is the resistance less than 5 ohms?
Yes No GO to HG7. REPAIR the open circuit. Clear the PCM DTCs.
REPEAT the self-test. - HG7 CHECK THE SUSPECT PCV HEATER CIRCUIT FOR A SHORT TO GROUND
Is the resistance greater than 10K ohms?
Yes No GO to HG8. REPAIR the short circuit. Clear the PCM DTCs.
REPEAT the self-test. - HG8 CHECK THE SUSPECT PCV CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) PCV Connector, Harness Side (-) PCVHC - Pin 1 Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the PCM DTCs.
REPEAT the self-test.GO to HG9. - HG9 CHECK THE RESISTANCE OF THE PCM CONTROLLED SUSPECT PCV HEATER
- Measure the resistance between:
(+) PCV Connector, Component Side (-) PCV Connector, Component Side IGN START/RUN - Pin 2 PCVHC - Pin 1
Is the resistance between 10 - 35 ohms?
Yes No GO to HG11. INSTALL a new PCV valve or tube. REFER to the appropriate Engine Emission Control article.
Clear the PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- HG10 PCV SYSTEM CHECK
- Start the engine and warm it until engine temperature is stable.
- Disconnect the closure (fresh air) hose from the remote air cleaner or air outlet tube (the tube connecting the mass airflow (MAF) sensor and the throttle body).
- Place a stiff piece of paper over the hose end. Wait 1 minute.
Does vacuum hold the paper in place?
Yes No The PCV system is OK.
RETURN to SYMPTOM CHARTS article for further direction.CHECK for vacuum leaks/obstruction in the PCV system (such as oil cap, PCV valve, hoses, cut grommets, valve cover bolt torque/gasket leak).
REFER to the appropriate Engine Emission Control article, Evaporative Emission (EVAP) Control System Vacuum Routing, for PCV system components and routing. REPAIR as necessary. - HG11 CHECK IF A CONCERN OR DTC IS STILL PRESENT
- Connect the PCV system.
- Clear the PCM DTCs.
- Carry out the PCM self-test.
Is the concern or DTC is still present?
Yes No GO to HG12. Unable to duplicate or identify the concern at this time.
RETURN to SYMPTOM CHARTS article for further direction. - HG12 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect all the PCM connectors and make sure they seat correctly.
- Carry out the PCM self-test.
- Verify the concern is still present.
Is the concern still present?
Yes No INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) , Programming the VID Block for a Replacement PCM. The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.