P0306 on 2011-2013 Dodge Journey 3.6L: Cylinder 6 Misfire Causes and Fixes

What's Unique About the 2011-2013 Dodge JOURNEY

While any car can have a misfire, early 3.6L Pentastar V6 engines used in the 2011-2013 Journey have a well-documented manufacturing defect with the left-bank cylinder head. The root cause was identified as excessive wear on the valve guides and seats, which were not sufficiently hardened. This leads to a loss of compression and triggers misfire codes specifically for cylinders 2, 4, and 6—all of which are on the left bank (front of the engine, toward the radiator in the Journey). This makes P0306 a potentially much more serious issue on this specific vehicle than on others. A secondary, but also common, issue on Pentastar engines is rocker arm failure, which can also lead to misfires.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Rough or shaky idle
• Hesitation or stumbling during acceleration
• Noticeable loss of engine power
• Flashing Check Engine Light (especially under load)
• Reduced fuel economy
• Engine running rougher than usual
• Ticking or tapping sound from the top of the engine, which could indicate rocker arm failure.

Most Likely Causes

1. Defective Left Cylinder Head 🔴 High Probability A known manufacturing defect in 2011-2013 3.6L Pentastar engines involved improperly hardened valve seats and guides on the left cylinder head (cylinders 2, 4, 6). This leads to premature wear, valve sealing issues, and a loss of compression. Chrysler issued Technical Service Bulletin #09-002-14 Rev. B and a warranty extension (X56) for this specific problem.
   How to confirm: A cylinder leak-down test is the definitive diagnostic method. 🎬 See how to perform and interpret a leak-down test. Per TSB #09-002-14 Rev. B, leakage of 25% or more in cylinder 6 confirms the failure. A visual inspection of the spark plug may also show rust or an orange/red color from coolant seeping into the cylinder, another sign of a head or head gasket issue.
   Typical fix: Complete replacement of the left cylinder head with an updated part (e.g., Mopar 68141353AC). The warranty extension was for 10 years/150,000 miles, which has now expired for all affected vehicles. 🎬 Watch: A guide to the left cylinder head warranty replacement.
   Est. part cost: $700-$2400
2. Faulty Ignition Coil 🟡 Medium Probability
   How to confirm: Swap the ignition coil from cylinder 6 with another cylinder (e.g., cylinder 4, which is also on the front bank and easier to access than odd-numbered cylinders on the rear bank). Clear the codes and drive the vehicle. If the code changes to P0304, the ignition coil is faulty. Resistance can also be tested; primary resistance should be 0.4-2.0 ohms and secondary should be 6k-10k ohms.
   Typical fix: Replace the faulty ignition coil. Cylinder 6 is on the front bank (towards the radiator), on the driver's side.
   Est. part cost: $20-$90
3. Worn or Fouled Spark Plug 🟡 Medium Probability
   How to confirm: Remove the spark plug from cylinder 6 and inspect it for wear, carbon buildup, oil fouling, or damage to the electrode. The recommended gap is approximately 0.044 inches.
   Typical fix: Replace the spark plug. It is recommended to replace all six spark plugs at the same time, especially if they are near their service interval.
   Est. part cost: $10-$25 per plug
4. Clogged or Faulty Fuel Injector ⚪ Low Probability
   How to confirm: If swapping the coil and plug doesn't resolve the issue, the fuel injector can be tested. With a multimeter, it should have a resistance of approximately 12.0-12.5 Ohms. It can also be swapped with another cylinder to see if the misfire follows, though this is more labor-intensive.
   Typical fix: Clean or replace the faulty fuel injector.
   Est. part cost: $50-$150

Rare But Worth Checking

• Failing Rocker Arm/Cam Follower: Another widespread issue on the 3.6L Pentastar is the failure of rocker arm bearings. This often starts with a ticking noise from the upper engine and can progress to a misfire code like P0306 and eventually cause camshaft damage.
• Intake Manifold Gasket Leak: A vacuum leak near cylinder 6 can lean out the air/fuel mixture and cause a misfire.
• Low Fuel Pressure: A failing fuel pump or clogged filter can cause misfires, but this would typically affect multiple cylinders and trigger other codes.
• Powertrain Control Module (PCM) Failure: In very rare cases, the PCM itself can be faulty, but all other possibilities should be exhausted before considering this.

Diagnosis Steps

1. Use an OBD-II scanner to confirm P0306 and check for any other related codes like P0300, P0302, or P0304.
2. Listen for a distinct ticking sound from the upper engine which could point towards a rocker arm issue.
3. Identify cylinder 6. On the transverse-mounted 3.6L in the Journey, the cylinders are numbered 1-3-5 on the rear bank (near firewall) and 2-4-6 on the front bank (near radiator). Cylinder 6 is on the driver's side of the front bank.
4. Swap the ignition coil from cylinder 6 with cylinder 4 (middle cylinder, front bank). Clear the codes, run the engine, and see if the misfire code changes to P0304. If it does, the coil is bad.
5. If the misfire remains on cylinder 6, remove and inspect the spark plug for wear, damage, or fouling. Look for a rust-colored or orange deposit, which indicates a coolant leak from a bad head gasket or cracked head. Replace if necessary.
6. If the coil and spark plug are good, the next step is critical for this vehicle: perform a cylinder leak-down test on cylinder 6. This test measures how well the cylinder can hold pressure.
7. If the leak-down test shows significant leakage (over 25%), the left cylinder head is almost certainly the cause, as documented in TSB #09-002-14 Rev. B.
8. If the leak-down test is good, further diagnostics on the fuel injector, wiring, rocker arms, and for vacuum leaks would be necessary.

Parts You'll Likely Need

• Left Cylinder Head Assembly (OEM #68141353AC) — This is the updated new part from Mopar to fix the known valve guide and seat issue. It supersedes the remanufactured part RL141353AC and several other previous numbers.
  Trusted brands: Mopar
  OEM price range: $1000-$2400
  Aftermarket price range: $700-$1500
• Ignition Coil (OEM #5149168AJ) — An ignition coil is a common failure point for misfires on most modern engines. This part number supersedes 5149168AI and 5149168AH.
  Trusted brands: Mopar, NGK, Bosch, Delphi
  OEM price range: $85-$130
  Aftermarket price range: $20-$70
• Iridium Spark Plug (OEM #SP149125AF) — Spark plugs are a routine maintenance item and can cause misfires when worn or fouled.
  Trusted brands: NGK, Champion, Bosch
  OEM price range: $20-$30
  Aftermarket price range: $10-$20

Related Codes That Often Appear With This One

• P0300 — This 'Random/Multiple Cylinder Misfire' code often appears if the cylinder head issue is beginning to affect other cylinders on the same bank, or if a rocker arm failure is progressing.
• P0302 / P0304 — These codes indicate misfires in cylinders 2 and 4. Seeing them with P0306 is a very strong indicator of the known left cylinder head issue, as all three cylinders (2, 4, 6) are on the affected bank.

Technical Service Bulletins (TSBs) & Recalls

• Bulletin #09-002-14 Rev. B (supersedes 09-002-14a): 'MIL Illumination: P0300, P0302, P0304 or P0306 (X56 Warranty Extension) This bulletin involves checking for excessive cylinder leakage and replacing the cylinder head if necessary.'
• Bulletin #09-002-14a: 'MIL Illumination: P0300, P0302, P0304 or P0306 (X56 Warranty Extension)'
• Bulletin #09-002-14: 'MIL Illumination: P0300, P0302, P0304 or P0306 (X56 Warranty Extension)'

Platform-Specific Known Issues

• A significant number of 2011-2013 models with the 3.6L V6 were subject to a known defect causing premature failure of the left cylinder head. This was acknowledged by Chrysler with Technical Service Bulletin #09-002-14 Rev. B, which describes checking for excessive cylinder leakage (>=25%) and replacing the head if necessary. The repair was covered under an extended warranty program (X56) for 10 years or 150,000 miles, which has now expired for these model years.

Mechanic-Grade Diagnostic Values

• Fuel Injector Resistance — expected: 12.0 - 12.5 Ohms. Failure: A reading significantly outside this range, or an open/shorted reading, indicates a faulty injector.
• Ignition Coil Primary Resistance — expected: 0.4 - 2.0 Ohms. Failure: A reading outside this range suggests a fault in the primary coil winding.
• Ignition Coil Secondary Resistance — expected: 6,000 - 10,000 Ohms (6kΩ - 10kΩ). Failure: A reading outside this range points to a failure in the secondary windings.

Hidden / Shadow Codes Worth Checking

• Mode $06, TID $53, CID $06: This is not a trouble code but a monitor within the PCM's diagnostic self-tests. It shows the raw count of misfire events for cylinder 6 for the current and last 10 driving cycles. This data can confirm an intermittent misfire on cylinder 6 even if the count isn't high enough to set the P0306 code. (see via A professional-grade scan tool or an advanced consumer OBD-II app that supports Mode $06 data display.)

Scan Tool Commands That Help

• wiTECH (Chrysler/Dodge Dealer Tool): OBDII Monitors > Misfire Mon SWC — To view live misfire counters for each cylinder to confirm which one is actively misfiring. This is the dealer tool equivalent of accessing Mode $06 data.
• wiTECH (Chrysler/Dodge Dealer Tool): PCM > Misc. Functions > Clear Mis-fire TLC — After a repair, this function can be used to clear the 'Trip Learn Counter' for the misfire monitor, which may be necessary to get the monitor to run and confirm the fix.

Wiring & Ground Locations

• PCM/TCM Power Relay — In the under-hood fuse box (Power Distribution Center), it is typically relay #144.. This single relay powers both the engine and transmission control modules. While a failure is unlikely to cause a single cylinder misfire, intermittent power loss could lead to erratic behavior and codes.
• Engine/Chassis Grounds — Key points include the main ground stud on the driver's side strut tower, the cable from that stud to the engine block, and a ground wire on the passenger side engine mount that connects to the passenger strut tower.. The Dodge Journey is noted by owners to have a weak ground system from the factory. Poor grounds can cause a wide range of electrical issues, including weak spark or erratic sensor readings that could contribute to a misfire code. Cleaning and upgrading these grounds is a common preventative measure.
• G904 / G924 — G904 is at the right rear of the engine compartment; G924 is at the lower right rear corner of the engine compartment.. These are factory ground points for various engine compartment components. Corrosion or looseness at these points can cause electrical faults.

Real Owner Repair Stories

• Dodge Journey Forum user (2011 Dodge Journey) — Check Engine Light with code P0306.
  ❌ Tried (didn't work) Not specified, user took it to the dealer.
  ✅ What actually fixed it The dealer diagnosed a defective cylinder head, which was replaced under the powertrain warranty.
• Dodge Journey Forum user (Dodge Journey 3.6L (year not specified)) — Loud clacking noise on cold start that quiets after 15-20 seconds.
  ✅ What actually fixed it This was a follow-up story *after* a cylinder head replacement was performed to fix a misfire. The user was now experiencing a new noise, possibly an exhaust leak or other issue resulting from the major repair, highlighting that even the correct fix can have complications.
• Reddit user r/dodgejourney (2011 Journey 3.5L (Note: different engine, but relevant ground issue)) — No crank, no start, tracing communication bus wiring issues.
  ❌ Tried (didn't work) Initial diagnosis focused on the communication bus itself.
  ✅ What actually fixed it Found a loose ground wire 'just hanging' near the passenger side engine mount. The wire connects a body ground post to the engine mount, and the ABS module is part of its loop. Reconnecting it solved the electrical problem.

OEM Part Supersession History

• 5149168AH, 5149168AI → 5149168AJ — Standard part revision and improvement for the ignition coil.
• RL141353AC (remanufactured) and other prior numbers → 68141353AC (new) — The original cylinder head design was defective. This updated part number represents the corrected design to fix the valve seat/guide issue.
• 05184085AC → RL184085AC (reman), 0280158233 (Bosch OEM) — Standard part lifecycle. The Bosch part number is the original equipment manufacturer's number.

Model Year Variations Within This Range

• 2011-2013: These model years are specifically known for the defective left cylinder head, which was the subject of TSB #09-002-14 and warranty extension X56. While later models can still have misfires, this specific, high-probability cause is unique to this early Pentastar production run.
• 2012-2014 (most common): While possible on any year, owner complaints and class-action lawsuits suggest that rocker arm failures are most prevalent in vehicles from the 2012-2014 model years.