P0303

(P0303) CYLINDER #3 MISFIRE

Part 1 Of 2:

Part 2 Of 2:

When Monitored and Set Condition
^ When Monitored: Any time the engine is running, and the Target Learning Coefficient has been successfully updated.
^ Set Condition: When more than a 1.0% misfire rate is measured during two trips.

POSSIBLE CAUSES
INTERMITTENT MISFIRE
ENGINE CONTROL RELAY OUTPUT CIRCUIT
INJECTOR DRIVER CIRCUIT
FUSED IGNITION SWITCH OUTPUT CIRCUIT
COIL ON PLUG DRIVER CIRCUIT
ENGINE MECHANICAL PROBLEM
COIL ON PLUG
SPARK PLUG
FUEL STRAINER PLUGGED
RESTRICTED FUEL SUPPLY LINE
FUEL PUMP
FUEL INJECTOR
POWERTRAIN CONTROL MODULE

Diagnostic Test
1. CHECK FOR CURRENT DTC





Turn the ignition on.
With the DRB III, read the PCM DTCs.
Is this DTC preset?
Yes>> For complete diagnosis of this DTC, P0301
No>> Go To 2

2. INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.

Note: Check connectors-Clean/repair as necessary. Poor pin to terminal connections can set DTCs. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors specific to this DTC. Wiggle the wires while checking for shorts and open circuits.

Note: Check for any Technical Service Bulletins that may apply.

Were there any problems found?
Yes>> Repair as necessary.
Perform Powertrain Verification Test - Ver 2
No>> The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.