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Service bulletin 18-048-26

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11031453
Published by NHTSA2026-04-22
Manufacturer's number18-048-26
Manufacturer's date2026-04-17
NHTSA componentPOWER TRAIN; ENGINE

NHTSA's summary

Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0300 - Multiple Cylinder Misfire (Active or Stored status set during cold start catalyst heating). ● P0301 - Cylinder 1 Misfire (Active or Stored status set during cold start catalyst heating). ● P0302 - Cylinder 2 Misfire (Active or Stored status set during cold start catalyst heating). ● P0303 - Cylinder 3 Misfire (Active or Stored status set during cold start catalyst heating). ● P0304 - Cylinder 4 Misfire (Active or Stored status set during cold start catalyst heating). ● P0305-00 - Cylinder 5 Misfire (Active or Stored status set during cold start catalyst heating). ● P0306-00 - Cylinder 6 Misfire (Active or Stored status set during cold start catalyst heating). Customers may also comment on one or more of the following: ● The vehicle has a rough idle. ● The engine has a miss. ● Noisy valvetrain. This bulletin involves reprogramming the PCM with the latest available software.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine, Transmission and driveline

Trouble codes named

P0300, P0301, P0302, P0303, P0304, P0305, P0306

Vehicles listed
JEEP WRANGLER2023

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
23V6410002023-09-18. POWER TRAIN:MANUAL TRANSMISSION
20230892023-02-23. Powertrain
23V1160002023-02-23. POWER TRAIN:CLUTCH ASSEMBLY
20226722022-11-23. Powertrain
22V8650002022-11-23. ENGINE

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
S26210000042026-10-07. Service bulletin. The Customer May Complain About a Popping Noise, Grinding Noise, or an Intermittent No Reverse or Forward Transmission Engagement. The Tech May Find Damaged and/or Worn Transmission Output Shaft Splines (850RE Transmission Only)
S26090000112026-09-17. Service bulletin. MIL-On and/or Engine Oil Leak
9100363 Rev 32026-09-03. Service bulletin. Turbocharger Kit Please note that many turbo components are serviceable separately and full turbo replacement may not be required. If the turbo is being inspected for: Noise/Rattle: Inspect heat shield fasteners for looseness and check the wastegate actuator/linkage for binding. The actuator kit is serviced separately. Oil Leak: Inspect the turbo oil feed O-ring area for leaks. O-ring is serviced separately.
1132712026-07-18. Service bulletin. CORE – HEATER
1132702026-07-18. Service bulletin. CORE – HEATER
1131532026-07-08. Service bulletin. THERMOSTAT – NONE.
1131522026-07-08. Service bulletin. THERMOSTAT – NONE.
1126392026-07-08. Service bulletin. THROTTLE BODY – NONE
1126402026-07-08. Service bulletin. THROTTLE BODY – NONE
S26090000092026-07-02. Service bulletin. Check Engine Light (CEL) Illuminated with Diagnostic Trouble Code (DTC) P0106 Manifold Absolute Pressure Sensor Performance Setting In The Powertrain Control Module (PCM)