Symptom Checks

Perform the following:

• Perform Key On Engine Off (KOEO) Self-Test. See step 1) of DIAGNOSTIC SUB-ROUTINES.
• Check ignition system. See IGNITION SYSTEMS in appropriate I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
• Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in appropriate TESTS W/CODES article in the ENGINE PERFORMANCE Section.
• Check idle speed. See IDLE SPEED in ADJUSTMENTS article in the ENGINE PERFORMANCE Section.
• Check PCV system. See EMISSION SYSTEMS & SUB-SYSTEMS in appropriate I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
• Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in appropriate I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
• Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in appropriate I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
• Check for restricted exhaust system.
• Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in appropriate I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
• Ensure engine operates at normal operating temperature.
• Check engine mechanical condition. Check compression, intake manifold gasket, camshaft and valve train components, etc.