JEEP
09-026-25
Manufacturer communications
- Publication date
- 2025-09-03
- Received by NHTSA
- 2025-09-10
- NHTSA record numbers
- 11023069
Manufacturer summary
Original wording in English
Not applicable to vehicles built for US market. Spark Plug Melting Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs):
• P0300 -00 - Random/Multiple Cylinder - Misfire Detected.
• P0301 -00 - Cylinder 1 - Misfire Detected.
• P0302 -00 - Cylinder 2 - Misfire Detected.
• P0303 -00 - Cylinder 3 - Misfire Detected.
• P0304 -00 - Cylinder 4 - Misfire Detected.
• P1336 -00 - Combustion misfiring (impact on catalytic converter) : Cylinder undetermined.
• P1337 - Combustion misfiring (impact on catalytic converter) : Cylinder 1.
• P1338 - Combustion misfiring (impact on catalytic converter) : Cylinder 2.
• P1339 - Combustion misfiring (impact on catalytic converter) : Cylinder 3.
• P1340 - Combustion misfiring (impact on catalytic converter) : Cylinder 4. Customers may also experience one or more of the following:
• Engine makes a loud metallic knocking noise at idle.
• Difficulty starting.
• Rough and noisy idle This bulletin involves inspecting for DTCs, inspecting for engine leaks and/or damage, and replacing the spark plugs.
• P0300 -00 - Random/Multiple Cylinder - Misfire Detected.
• P0301 -00 - Cylinder 1 - Misfire Detected.
• P0302 -00 - Cylinder 2 - Misfire Detected.
• P0303 -00 - Cylinder 3 - Misfire Detected.
• P0304 -00 - Cylinder 4 - Misfire Detected.
• P1336 -00 - Combustion misfiring (impact on catalytic converter) : Cylinder undetermined.
• P1337 - Combustion misfiring (impact on catalytic converter) : Cylinder 1.
• P1338 - Combustion misfiring (impact on catalytic converter) : Cylinder 2.
• P1339 - Combustion misfiring (impact on catalytic converter) : Cylinder 3.
• P1340 - Combustion misfiring (impact on catalytic converter) : Cylinder 4. Customers may also experience one or more of the following:
• Engine makes a loud metallic knocking noise at idle.
• Difficulty starting.
• Rough and noisy idle This bulletin involves inspecting for DTCs, inspecting for engine leaks and/or damage, and replacing the spark plugs.
Reported code forms
Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
Jeep
P0300 -00Random/Multiple Cylinder - Misfire DetectedJeep
P0301 -00Cylinder 1 - Misfire DetectedJeep
P0302 -00Cylinder 2 - Misfire DetectedJeep
P0303 -00Cylinder 3 - Misfire DetectedJeep
P0304 -00Cylinder 4 - Misfire DetectedJeep
P1336 -00Combustion misfiring (impact on catalytic converter) : Cylinder undeterminedJeep
P1337Combustion misfiring (impact on catalytic converter) : Cylinder 1Jeep
P1338Combustion misfiring (impact on catalytic converter) : Cylinder 2Jeep
P1339Combustion misfiring (impact on catalytic converter) : Cylinder 3Jeep
P1340Combustion misfiring (impact on catalytic converter) : Cylinder 4Check vehicle applicability
A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.