Knock Sensor: Testing and Inspection

Fig. 4 Knock control system, checking timing retard.:

1. Warm engine to normal operating temperature and run at idle.
2. Connect timing light to the "L-1" (lead) high tension lead Fig. 4.

Fig. 32 Tapping engine hanger with plastic hammer.:

3. Tap engine hanger lightly with plastic hammer,Fig. 32. and ensure ignition timing does not move.
4. Connect jumper wire to terminals of initial set coupler.
5. Tap engine hanger lightly with plastic hammer and ensure ignition timing retards.
6. Disconnect jumper wire from initial set coupler.
7. Perform same test for trailing side.