Test Procedure
- HU1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS)
Is DTC P0505 or P0506 present?
Yes No GO to HU2 . For symptoms without DTCs, GO to HU2 .
For all others, RETURN to ENGINE CONTROLS - SYMPTOM CHARTS (HYBRID) for further direction. - HU2 CHECK THE INTAKE AIR SYSTEM FOR LEAKS, OBSTRUCTIONS, AND DAMAGE
- Listen for vacuum leaks from the following:
- loose connections on the intake air tube at the air cleaner housing or throttle body
- cracked or punctured intake air tube
- worn gaskets between the mass air flow (MAF) sensor and the air cleaner assembly
- vacuum supply connectors and hose
- intake manifold assembly or gasket
- exhaust gas recirculation (EGR) valve gasket leak to intake manifold
- verify the integrity of the positive crankcase ventilation (PCV) system and the correct PCV valve part number
- correctly seated engine oil dipstick, tube or oil fill cap
- aftermarket accessories and performance modifications
Are any concerns present?
Yes No REPAIR as necessary.
Clear the PCM DTCs. REPEAT the self-test.GO to HU3 . - Listen for vacuum leaks from the following:
- HU3 CHECK THE THROTTLE BODY FOR EXCESSIVE WEAR
- Ignition OFF.
- Remove the throttle body assembly. Refer to the Fuel Charging and Controls article.
- Inspect the throttle body for:
- excessive wear or grooving in the throttle bore
- misaligned or worn throttle plate
- excessive gap between the throttle bore and plate
Are any concerns present?
Yes No INSTALL a new throttle body assembly.
REFER to the Fuel Charging and Controls article.
Clear the PCM DTCs. REPEAT the self-test.RETURN to ENGINE CONTROLS - SYMPTOM CHARTS (HYBRID) for further direction.