System Quick Check (Engine Will Not Start)
Pretest condition: engine will not startIf the engine does not start, the most fundamental step in trouble shooting the ignition system is to determine whether or not the system is creating any kind of spark at the spark plug. If a spark is present, it is the ignition systems efficiency/accuracy or another system's function that is in question. If no spark is present, more detailed testing of wiring, connections, battery or individual components is needed.
NOTE: Battery must be fully charged and terminals must be in good condition for all tests.
1. To check for spark, turn ignition OFF.
2. Remove a spark plug wire.
3. Connect it to a good (preferably new) spark plug and hold the outer electrode, with insulated pliers, to ground.
WARNING: Use insulated pliers to test spark plug, other equipment may cause bodily harm or death.
4. Have a helper crank the starter. Look for spark in the plug gap.
a. If a bright blue spark is available, ignition system is healthy, fault may lie in the fuel, computerized engine control or other related system. End of test.
b. A yellow/orange spark is weaker and indicates that ignition system is not operating at peak efficiency. Check such components as the coil/plug wires, cap and rotor. If no fault can be found, check the rest of the ignition system components.
c. If there is no spark, check the wiring to ignition coil, also check the ignition switch (refer to BODY ELECTRICAL SAFETY AND ENTERTAINMENT), ignition coil, Hall effect sender and ignition (Hall) control unit. If no fault found, check all other ignition components.
5. For additional trouble shooting information refer to DIAGNOSIS BY SYMPTOM.
6. Reconnect spark plug wire.