Diagnosis & Testing


Prior to diagnosis or testing procedures, visually inspect the components of the ignition and engine control systems. Check for the following:

Discharged battery or low alternator output
Damaged, corroded, or loose electrical connections
Damaged or worn electrical insulation
Poor spark plug connections
Ignition module multi-connector condition
Blown fuses
Damaged or corroded ignition wires
Excessively worn, defective, or damaged spark plugs

Check the spark plug wires and boots for signs of poor insulation that could cause shorting or crossfiring. Make sure the battery is fully charged and that all accessories are off during diagnosis and testing. Make sure the idle speed is properly adjusted and within specification. Check all of the fuel injector electrical connections..