JEEP
18-058-26
Manufacturer communications
- Publication date
- 2026-06-04
- Received by NHTSA
- 2026-06-16
- NHTSA record numbers
- 11033868
Manufacturer summary
Original wording in English
Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one of the following Diagnostic Trouble Codes (DTCs):
• P1CEA - Boost Side Evap Purge System Performance.
• P0300-00 - Random/Multiple Cylinder Misfire Detected
• P0301-00 - Cylinder 1 Misfire
• P0302-00 - Cylinder 2 Misfire
• P0303-00 - Cylinder 3 Misfire
• P0304-00 - Cylinder 4 Misfire Customers may also experience one or more of the following:
• Engine RPM fluctuations at low vehicle speeds after extended idling.
• An ignition-off draw or battery drain condition.
• Sluggish engine performance and misfires.
• Engine knocking when the accelerator is pressed hard or quickly This bulletin involves inspecting and possibly reprogramming the PCM and Transmission Control Module (TCM) with the latest available software.
• P1CEA - Boost Side Evap Purge System Performance.
• P0300-00 - Random/Multiple Cylinder Misfire Detected
• P0301-00 - Cylinder 1 Misfire
• P0302-00 - Cylinder 2 Misfire
• P0303-00 - Cylinder 3 Misfire
• P0304-00 - Cylinder 4 Misfire Customers may also experience one or more of the following:
• Engine RPM fluctuations at low vehicle speeds after extended idling.
• An ignition-off draw or battery drain condition.
• Sluggish engine performance and misfires.
• Engine knocking when the accelerator is pressed hard or quickly This bulletin involves inspecting and possibly reprogramming the PCM and Transmission Control Module (TCM) with the latest available software.
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 MisfireJeep
P0302-00Cylinder 2 MisfireJeep
P0303-00Cylinder 3 MisfireJeep
P0304-00Cylinder 4 Misfire Customers may also experience one or more of the followingJeep
P1CEABoost Side Evap Purge System PerformanceCheck vehicle applicability
A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Jeep | GRAND CHEROKEE | 2026 |
| Jeep | GRAND CHEROKEE L | 2026 |