{"nhtsa_id":11033868,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2026-06-16","date":"2026-06-04","document_id":"18-058-26","mfr_campaign":null,"replaces":null,"component":"POWER TRAIN","mfr_system":null,"summary":"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.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2026/MC-11033868-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2026/MC-11033868-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/11033868","components":[{"id":"powertrain","name":"Transmission and driveline","parent":null}],"codes":["P0300","P0301","P0302","P0303","P0304","P1CEA"],"topics":[],"vehicles":[{"make":"JEEP","model":"GRAND CHEROKEE","year_from":2026,"year_to":2026,"match":"exact","vehicle_ids":["2026_jeep_grand-cherokee"]},{"make":"JEEP","model":"GRAND CHEROKEE L","year_from":2026,"year_to":2026,"match":"exact","vehicle_ids":["2026_jeep_grand-cherokee-l"]}],"as_of":"2026-10-19","note":"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.","attribution":[]}