FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0304







P0304 - CYLINDER #4 MISFIRE









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.





For a complete Powertrain Control Module Circuit Diagram, Schematics and Diagrams.

Diagnostic Test

1. CHECK FOR CURRENT DTC
Turn the ignition on.
With the scan tool, read PCM DTCs.
Is this DTC present?

Yes

- For complete diagnosis of this DTC, refer to (P0301) CYLINDER #1 MISFIRE. 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. Powertrain Verification Test

No

- The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.