Cold Start Ignition Timing Performance
During cold-start the ECU retards ignition timing to raise exhaust temperature for catalyst light-off. The strategy does not deliver the expected timing - feedback from knock sensor or combustion model shows ignition too far advanced or retarded for the demanded calibration.
Affected components
- Ignition timing strategy
- Knock sensor
- Cam position sensor
Common causes
- High likelihood: Knock sensor drift causes wrong feedback
- Medium likelihood: Cam phaser offset against crank
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.