Back to 2002 Mazda B2300

2002 MAZDA B2300

2.3L I4FWDAUTOMATICgas
Repairs0Labor467Torque2446Fluid6DTC697Battery0Maintenance0Recalls0
P1309high severityPowertrain

Misfire Detection Monitor

on 2002 Mazda B2300 2.3L 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

  1. Check for companion cylinder-specific misfire codes
  2. Inspect CMP sensor and synchronizer alignment
  3. Test spark plugs and ignition coils
  4. Perform fuel injector balance test
  5. Run compression test

Repair notes

Verify CMP synchronizer alignment and diagnose the root cause of the misfire.

Other Powertrain codes on this vehicle

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