Symptom Checks

Check the following items:

• Check cooling system for overheating. If cooling system is overheating, repair as necessary. See appropriate article in ENGINE COOLING.
• Check Mass Air Flow (MAF) sensor input to PCM. See TEST DC , step 25)  under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
• Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. See appropriate article in ENGINES.
• Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
• Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
• Check PCV system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
• On models with Knock Sensor (KS), check KS input to PCM. See TEST DG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
• Check air intake system. Check engine oil quality. If no problems are indicated, return to SYMPTOM DIAGNOSIS  to identify any additional symptoms or see TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.