P1309high severityPowertrain
Misfire Detection Monitor
on 1998 Mazda B2500 2.5L I4 · FWD
What this code means
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.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1