Knock sensor 1 signal voltage is too low (short to ground / dead sensor). The DME loses knock data and retards timing as a safeguard.
SYMPTOMS
- Check-engine light
- Reduced power
- Worse economy
- Possible audible knock under load
LIKELY CAUSES
- Failed or flooded knock sensor
- Wiring short to ground
- Corroded connector
- Moisture intrusion
DIAGNOSIS STEPS
- Check sensor resistance and wiring
- Inspect connector for water/corrosion
- Verify torque on the sensor mount
- Replace
RELATED PARTS
- Knock sensor
- Harness