Retard Function

Retard Function Inspection:

1. Warm engine to operating temperature.
2. Turn all electrical loads "OFF."
3. Connect a tachometer and timing light.
4. Run at idle and check that ignition timing is within specification at 12° ± 1° BTDC.
5. Disconnect service connector (White: 1-pin) at ECU.
6. Tap on intake manifold with a plastic hammer and ensure that timing retards.
7. Check that timing returns to specification when tapping is stopped.
8. If timing does not change, check knock sensor as described in this section. Also check for faulty connections, open or shorted wires, etc.