October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.
Possible Causes & Corrections
- Ensure EGR valve is not stuck open.
- Check engine for sticking or leaking valves.
- Check for proper valve timing.
- Check for engine vacuum leaks. Ensure engine is tuned to specifications.
- Using Spark Tester (J-26792), check available output voltage of ignition coil.
- Check for crossfire between spark plugs, distributor cap and spark plug wires.
- Check for an intermittent ignition system problem.
- Check for erratic spark timing or distributor reference (RPM) signal.
- Ensure initial ignition timing is properly set.
- Check for fuel or water in vacuum hose to MAP sensor. Also check for restricted hose.