Symptom Checks

Perform the following:

• Check cooling system. If cooling system is overheating, go to ENGINE RUNS HOT (OVERHEATING) symptom.
• Check base timing. See DIAGNOSTIC SUB-ROUTINES.
• Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
• Check fuel delivery system. See FUEL SYSTEM in appropriate SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE section.
• Check Exhaust Gas Recirculation (EGR) system. See EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE section.
• Check Positive Crankcase Ventilation (PCV) system. See EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE section.
• Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE section.
• Ensure transmission is functioning properly.