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P0301 on the 2026 Jeep Grand Cherokee

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

Bulletins for this model year that name P0301
09-013-26 REV. A2026-10-07. Service bulletin. Engine Runs Rough Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● 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 comment on the following: ● Engine runs rough. This bulletin involves replacing all four main chamber spark plugs.
09-023-262026-09-30. Service bulletin. Umbrella Valve Seal Missing From Cylinder Head Cover Vehicle may exhibit a MIL-ON. SYMPTOM: Upon inspection the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have set: ● 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. This bulletin involves inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover.
09-020-262026-08-26. Service bulletin. Umbrella Valve Seal Missing From Cylinder Vehicle may exhibit a MIL-ON. SYMPTOM: Upon inspection the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have set: ● 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. This bulletin involves inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover.
09-017-26 REV. A2026-08-26. Service bulletin. Umbrella Valve Seal Missing From Cylinder Head Cover Customer may experience a MIL-ON and/or an indication of low engine oil level. SYMPTOM: Upon inspection the technician may find the following: 1. One or more of the following Diagnostic Trouble Codes (DTCs) have set: ● 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. 2. Engine oil level is low. IMPORTANT! If none of above symptoms are present, this TSB does NOT apply. This bulletin involves inspecting the engine oil level, possibly inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover.
09-017-262026-08-13. Service bulletin. Umbrella Valve Seal Missing From Cylinder Head Cover Customer may experience a MIL-ON and/or an indication of low engine oil level. SYMPTOM: Upon inspection the technician may find the following: 1. One or more of the following Diagnostic Trouble Codes (DTCs) have set: ● 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. 2. Engine oil level is low. IMPORTANT! If none of above symptoms are present, this TSB does NOT apply. This bulletin involves inspecting the engine oil level, possibly inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover
09-013-262026-07-18. Service bulletin. Engine Runs Rough Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● 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 comment on the following: ● Engine runs rough. This bulletin involves replacing all four main chamber spark plugs.
18-058-262026-06-16. Service bulletin. 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.

7 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.