Description

DATA TROUBLE CODE: P0300

SYSTEM: Random Misfire Detected

CIRCUIT DESCRIPTION
Misfire: The ECM uses the Crankshaft Position Sensor and Camshaft Position Sensor to monitor changes in the Crankshaft Rotation for each cylinder.
The ECM counts the number of times the engine speed change rate indicates that misfire has occurred. And when the misfire rate equals or exceeds the count indicating that the engine condition has deteriorated, the MIL lights up.
If the misfire rate is high enough and the driving conditions will cause catalyst overheating, the MIL blinks when misfiring occurs.

DIAGNOSTIC TROUBLE CODE DETECTING CONDITION
- Misfiring of multiple cylinders is detected during the same 200 or 1,000 revolutions.

TROUBLE AREA
- Ignition system.
- Injector.
- Fuel line pressure.
- EGR.
- Compression pressure.
- Valve clearance not to specification.
- Valve timing.
- Mass Air Flow Meter.
- Engine Coolant Temperature Sensor.

NOTE: When the code for a misfiring cylinder is recorded repeatedly but no Random Misfire code is recorded, it indicates that the misfires were detected and recorded at different times.