Ignition System

Description and Operation

Description

Ignition timing is controlled by the electronic spark advance control system. Standard reference ignition timing data for engine operating conditions are preprogrammed in the memory of the ECM (Engine Control Module). Engine operating conditions (engine speed, load, warm-up condition, etc.) are detected by various sensors. Based on these sensor signals and the ignition timing data, signals are sent to the ECM to interrupt the primary current. The ignition coil is activated and timing is controlled.

Repair Procedures

Inspection on Vehicle

Inspect the ignition coil assembly and perform the spark test.

1. 1
   Check for DTCs.
2. 2
   Check for spark.

   1. Remove the engine cover.
   2. Remove the cylinder head cover center cover.
   3. Remove the ignition coils.
   4. Using a spark plug socket, remove the spark plugs.
   5. Disconnect the 3 injector connectors.
   6. Ground the spark plug to the engine.

      

   7. Check for spark at each spark plug while cranking the engine.
3. 3
   If no sparks occur, perform the following check.

   

4. 4
   Using a spark plug socket, install the spark plugs.
5. 5
   Install the ignition coils.
6. 6
   Install the center cylinder head cover and engine cover.

Troubleshooting

Troubleshooting

Symptom	Suspected Area	Remedy
Engine Does Not Start or Is Hard to Start Starts (Starts Normally)	Ignition Switch	Inspect the ignition switch or replace if necessary.
	Ignition Coil	Inspect the ignition coil or replace if necessary.
	Spark Plugs	Inspect the spark plugs or replace if necessary.
	Ignition wiring is disconnected or damaged.	Repair the wiring or replace if necessary.
Rough idle or stall	Ignition Wiring	Repair the wiring or replace if necessary.
	Ignition Coil	Inspect the ignition coil or replace if necessary.
Engine shakes / poor acceleration	Spark plugs and spark plug cables	Inspect spark plugs / cable or replace if necessary
	Ignition Wiring	Repair the wiring or replace if necessary.
Poor mileage	Spark plugs and spark plug cables	Inspect spark plugs / cable or replace if necessary