FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0304

DTC P0304 Cylinder 4 - Misfire Detected

DESCRIPTION
Misfires can be caused by lack of combustion in a cylinder due to absence of spark, poor fuel metering, poor compression, or many other causes. Even a small number of misfires may result in excessive exhaust emissions due to the unburned mixture. Increased misfire rates cause damage to the catalytic converter. The ECM monitors the crankshaft speed variation to determine if any misfires generated. The ECM identifies the specific cylinder in which the misfire has occurred and counts individual misfire events by monitoring changes in the crankshaft rotation for each cylinder. A random misfire indicates two or more cylinders are misfiring.

DTC Detecting Condition:






Schematic Diagram:






Step 1 - 2:




Step 3 - 5:




Step 6 - 8:




Step 8 (continued):




INSPECTION PROCEDURE