Knock Sensor Test
- Turn ignition on. Engine warning light (on instrument panel) should come on. Start engine and accelerate engine to 3000 RPM (one time only). Engine warning light must go off. If light goes out, test is completed.
- If light does not go out, install a fuse in test terminals of fuel pump relay for a minimum of 3 seconds. See Fig 1. Engine warning light must start blinking. If light stays on, go to TIMING ADVANCE TEST .
- If light blinks in intervals of 2, the knock sensor circuit is defective. Check knock sensor tightness. If loose, tighten knock sensor to 10 ft. lbs. (14 N.m). Check for open circuit in knock sensor wiring. If wiring is okay, knock sensor or Hall control unit is defective.
- If light blinks in intervals of 3, check White vacuum hose to electronic ignition control unit for damage. Check for faulty throttle switches. See IDLE & FULL THROTTLE SWITCH TEST - 4000S . If okay, pressure sensor in unit is faulty.