P1309
Misfire Detection Monitor Not enabled
Severity
⚠️ MediumCan you drive?
Yes, but get it checked soon
Approx. repair cost
$6–56 (est.)
Symptoms
- Check Engine light comes on
- Increased fuel consumption
- Unstable engine idling
- Reduced engine power
- The vehicle may fail emissions tests
Causes
- Malfunction of misfire detection sensors
- Open or short circuit in the sensor circuit
- Problems with ECU software
- Recently cleared fault codes or replaced the ECU
- Poor contact in sensor connectors
How to Fix
- Check the condition and connection of misfire detection sensors
- Check the integrity of the sensor circuit
- Scan the ECU for other errors
- Update or reflash the ECU software
- Check the condition of the connectors and wiring harness