2021-2025 Jeep, Dodge, RAM Misfire DTCs and Rough Idle TSB

Owners of various 2021-2025 Jeep, Dodge, and RAM vehicles equipped with the 3.6L PSU Long Block engine may encounter issues such as "misfire DTC codes", rough idle, or valvetrain noise. This manufacturer communication, identified as GPOP - Issue Review System, outlines a software-related solution to these problems.

Symptoms

Vehicle owners might observe their vehicle exhibiting one or more of the following symptoms:

• Misfire DTC codes: Diagnostic Trouble Codes related to engine misfires may be stored in the vehicle's computer system.
• Rough idle: The engine may run unevenly or vibrate excessively when idling.
• Valvetrain noise: Unusual noises originating from the engine's valvetrain components.

These symptoms are often linked to the vehicle's oil pump operation mode, specifically during engine start-up.

Diagnosis and Trigger Conditions

The root cause of these issues is related to the calibration and software managing the oil pump's high-pressure mode during engine start-up. The GPOP - Issue Review System document, referencing SOL # S2509000004, indicates that an outdated calibration can lead to the described symptoms, including the presence of "misfire DTC codes".

Repair Procedure Summary

The recommended repair involves updating the vehicle's calibration/software to ensure the oil pump operates correctly in high-pressure mode during engine start-up. Many 25MY (Model Year 2025) and beyond RU, VF, WL, and WD vehicles already incorporate the latest oil pump mode. For 24MY (Model Year 2024) vehicles, service releases are available. Specifically, JL and JT models received updates as a running change on August 15, 2024, and August 19, 2024, respectively. DT models are updated starting from 25MY and beyond.

If you own a 24MY vehicle experiencing "misfire DTC codes" or other related symptoms and a service release is available, it is crucial to follow the released service procedures to update to the corresponding calibration or software.

Important Warnings

It is important to confirm that any vehicle being repaired has the latest calibration/software update for the oil pump operation mode. This ensures the high-pressure mode functions correctly during engine start-up. For 24MY vehicles where a service release is available, technicians must follow the specific service procedures to apply the correct calibration/software update.

Owner Action

If your 2021-2025 Jeep, Dodge, or RAM vehicle is experiencing "misfire DTC codes", rough idle, or valvetrain noise, it is recommended to contact your authorized dealership. They can check if your vehicle requires the latest calibration/software update for the oil pump operation mode, as outlined in the GPOP - Issue Review System. This update is designed to resolve the underlying issue causing the symptoms.

Source: NHTSA ID: 11018451