FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0304

Tests 1 - 2:




Tests 3 - 6:




Tests 7 - 10:




Tests 11 - 12:




SYMPTOM
P0304-CYLINDER #4 MISFIRE

TEST NOTE
This symptom is diagnosed using the test P0300-MULTIPLE CYLINDER MIS-FIRE.

WHEN MONITORED
Any time the engine is running, and the adaptive numerator has been successfully updated.

SET CONDITION
When more than a 2% (2.5% LEV) misfire rate is measured during two trips, or with a 10% to 30% misfire rate during one trip.

POSSIBLE CAUSES
- Mis-Fire Conditions No Longer Exist
- Fuel System Problem
- Secondary Ignition Or Mechanical Problem
- Erratic CAM/CRANK Sensor Signals
- Engine Mechanical Problem
- Other Possible Causes For Mis-Fire