P0300 on Jeep Gladiator
Random/Multiple Cylinder Misfire Detected
Methodology: Reviewed against the SAE J2012 generic DTC definition and NHTSA owner-complaint patterns, then scoped to Jeep Gladiator context without treating complaints as confirmed diagnoses.
Sources: SAE/OBD-II definitions, manufacturer service information, and public reliability reports (including NHTSA where applicable).
- SAE J2012 Diagnostic Trouble Code Definitions — Generic diagnostic trouble code definition reference for P0300.
- NHTSA recalls, complaints, and manufacturer communications — Used to check public owner complaint context, recall status, and safety-related manufacturer communications by VIN or vehicle.
Limits: Guidance is informational and may not match every model-year or revision. Confirm with the official manual and diagnostics before replacing parts. For safety-critical or electrical work, use a qualified technician.
What P0300 Means on Your Jeep Gladiator
P0300 is a diagnostic trouble code indicating: Random/Multiple Cylinder Misfire Detected. This code relates to the ignition system system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.
Real Jeep Gladiator Owner Reports
Source: NHTSA Complaints Database
"To Whom It May Concern, I hope this message finds you well. I am writing to formally report a serious mechanical failure involving my 2020 Jeep Gladiator (VIN: [XXX] ), which recently experienced a complete engine lock-up without any prior warning signs. The vehicle is now inoperable."
"To Whom It May Concern, I am writing to formally report a serious mechanical issue involving my 2020 Jeep Gladiator (VIN: [XXX] rienced a complete and unexpected engine lock-up. The vehicle is now undrivable and presents both a functional and potential safety concern."
"Error Codes P0300, 301,305, 420. Driving on the interstate I got the CEL light. One point during driving when the 420 code came in vehicle went into limp mode and speed was greatly reduced in 70 mph traffic. Luckily I was able to get to the side of the road so no accident happened."
"Starting at just over 100 miles my vehicle started displaying a electronic start/stop systems errors and the check engine light came one. the cel was caused by engine misfires and show code p0300."
"On my 2020 jeep gladiator rubicon ess and check engine light came on at 249 miles. check engine light code was p0300 multiple cylinder misfire. took it to the dealer monroe dodge and they replaced the battery for ess and did a recommended pcm flash for the check engine light."
All reports filed by vehicle owners directly with the U.S. Department of Transportation.
📊 Complaint Trend by Model Year
Common Causes on Jeep Gladiator
Based on NHTSA complaint component analysis for this vehicle.
What To Do Next
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1
Check for recalls on YOUR VIN
Go to nhtsa.gov/recalls and enter your VIN. If your vehicle is covered, repairs are free.
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2
Get a proper diagnosis
A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50–$150) pinpoints the root cause before you spend money on parts.
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3
Compare repair quotes
Get 2–3 quotes. Dealer vs. independent shop prices often differ 30–50% for the same repair.