Spark Knock
- Check ignition system. See BASIC TESTING - 4-CYL article in the ENGINE PERFORMANCE section.
- Check for vacuum leaks.
- Check EGR system. See I - SYSTEM/COMPONENT TESTS - EEC (2.5L) article and TESTS W/CODES - EEC 2.5L article in the ENGINE PERFORMANCE section.
- Perform QUICK TEST. See TESTS W/CODES - EEC 2.5L article in the ENGINE PERFORMANCE section.
- Check cooling system for overheating.