Symptom Checks

Check the following items:

• Perform QUICK TEST. See the TESTS W/CODES - EEC-V article. If code present, perform appropriate CIRCUIT TEST.
• Check cooling system for overheating. If cooling system is overheating, go to ENGINE RUNS HOT symptom.
• Check ignition timing. See ADJUSTMENTS article.
• Check EGR system. See the SYSTEM & COMPONENT TESTING - EEC-V article.
• Check engine compression. Check engine mechanical condition. Check intake manifold gasket, camshaft and valves.
• Check ignition system. See CIRCUIT TEST JB in the TESTS W/CODES - EEC-V article.
• Check PCV system. See CIRCUIT TEST HG in the TESTS W/CODES - EEC-V article.
• Check octane adjust system. See step 5) of CIRCUIT TEST FG in the TESTS W/CODES - EEC-V article. If available, check Technical Service Bulletins (TSBs) for OCT ADJ information.