Misfire Detection Monitor
2014-2021 Mazda Mazda6 2.5L I4
Description
The PCM misfire detection monitor has identified a misfire condition but cannot pinpoint the specific cylinder. The CMP sensor synchronizer may not be providing the signal needed for cylinder-specific misfire identification.
Symptoms
- Check Engine Light
- Engine misfires
- Rough running
- Reduced power
- Failed emissions test
Common Causes
- Faulty CMP sensor or synchronizer
- Worn spark plugs or ignition coils
- Fuel injector malfunction
- Low compression in one or more cylinders
- Vacuum leak at specific cylinder
Diagnostic Steps
- Check for companion cylinder-specific misfire codes
- Inspect CMP sensor and synchronizer alignment
- Test spark plugs and ignition coils
- Perform fuel injector balance test
- Run compression test
Repair Notes
Verify CMP synchronizer alignment and diagnose the root cause of the misfire.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1309 on Other Vehicles
Common Questions
What does code P1309 mean on a 2014-2021 Mazda Mazda6?
P1309 stands for "Misfire Detection Monitor". The PCM misfire detection monitor has identified a misfire condition but cannot pinpoint the specific cylinder. The CMP sensor synchronizer may not be providing the signal needed for cylinder-specific misfire identification.
What are the symptoms of P1309 on a Mazda Mazda6?
Common symptoms of P1309 include: Check Engine Light, Engine misfires, Rough running, Reduced power, Failed emissions test.
What causes P1309 on a 2014-2021 Mazda Mazda6?
Common causes of P1309 include: Faulty CMP sensor or synchronizer, Worn spark plugs or ignition coils, Fuel injector malfunction, Low compression in one or more cylinders, Vacuum leak at specific cylinder.