P0306 on Jeep Wrangler
Cylinder 6 Misfire Detected
Methodology: Reviewed against the SAE J2012 generic DTC definition and NHTSA owner-complaint patterns, then scoped to Jeep Wrangler 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 P0306.
- 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 P0306 Means on Your Jeep Wrangler
P0306 is a diagnostic trouble code indicating: Cylinder 6 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 Wrangler Owner Reports
Source: NHTSA Complaints Database
"I started my 2008 jeep wrangler jk and immediately got a check engine light with an audible sound. the engine was running very rough and shaking. i turned off the engine and it seemed fine but the check engine light was still on. i have a obd2 diagnostic code reader and it showed the code p0306."
"Vehicle is currently (dec 2012) at dealer having heads/valves replaced (10th day after waiting 10 days for parts), original report 9 nov: idling engine continues to be very rough, much rougher than when reported to dealer on november 9 2012, dealer did pcm reflash/update as stalling maneuver, after"
"P0302 misfire cylinder 2. p0300, p0304 & p0306 jeep/dodge is very aware of this cylinder issue and has a service bulletin for several models. (journey, wrangler, 200/avenger, challenger, charger, grand caravan, durango and grand cherokee). and they will not recall this part."
"Mil is illuminated periodically for dtc p0306. low compression detected in cylinder 6."
"The car began to idle roughly--it would rattle and shake just sitting at a red light. if i tried to just roll the vehicle slightly forward, it would stutter. check engine light came on, but the manual informs to wait a few drive cycles to see if it will just turn off."
All reports filed by vehicle owners directly with the U.S. Department of Transportation.
📊 Complaint Trend by Model Year
Common Causes on Jeep Wrangler
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.