P0306 on 2011-2018 Dodge Challenger: Cylinder 6 Misfire Causes & Fixes

What's Unique About the 2011-2018 Dodge CHALLENGER

For the Dodge Challenger, the cause of a P0306 code is highly dependent on the engine. On early 3.6L Pentastar V6 models (2011-2013), P0306 is one of the specific codes listed in Technical Service Bulletin 09-002-14 REV. B for a known left cylinder head defect. This issue was so prevalent that Chrysler issued an extended warranty (X56) to cover the repair, which involves replacing the head if a leak-down test shows over 25% leakage. For the 5.7L and 6.4L Hemi V8 engines, while standard ignition issues are common, a P0306 could also be an early sign of the infamous 'Hemi tick,' which is often a failing lifter roller that can lead to camshaft damage if ignored. 🎬 Watch a full walkthrough of the Hemi lifter and camshaft replacement. This is often attributed to oiling issues during extended idling or at low RPMs.

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 vibrating idle
• Noticeable loss of engine power and sluggish acceleration
• Hesitation or stumbling when accelerating
• Flashing or solid Check Engine Light
• Increased fuel consumption
• Engine may sound unbalanced or shaky
• A distinct ticking or tapping noise from the top of the engine (in the case of Hemi lifter failure).

Most Likely Causes

1. Faulty Ignition Coil 🔴 High Probability
   How to confirm: Swap the ignition coil from cylinder 6 with another cylinder (e.g., cylinder 4). Clear the codes and drive the vehicle. If the code changes to P0304, the coil is bad.
   Typical fix: Replace the faulty ignition coil. It is often recommended to replace the corresponding spark plug at the same time.
   Est. part cost: $30-$75
2. Worn or Defective Spark Plug 🔴 High Probability
   How to confirm: Remove and inspect the spark plug from cylinder 6. Look for signs of wear, fouling (oily, sooty, or white deposits), or incorrect gap. A dropped plug can also have a closed gap, causing a misfire.
   Typical fix: Replace the spark plug. Hemi engines have two spark plugs per cylinder, so be sure to check and replace both if necessary. It's best practice to replace all spark plugs at once if they are near the end of their service life.
   Est. part cost: $5-$25 per plug
3. Left Cylinder Head Failure (2011-2013 3.6L V6) 🔴 High Probability An acknowledged manufacturing defect caused premature wear of valve guides and seats on the left cylinder head (cylinders 2, 4, and 6). TSB #09-002-14 REV. B was issued for this specific problem, which was covered by the X56 warranty extension for 10 years/150,000 miles.
   How to confirm: A cylinder leak-down test must be performed on cylinders 2, 4, and 6. According to the TSB, leakage of 25% or greater confirms the failure. Hearing air escape from the exhaust during the test is a strong indicator of a bad exhaust valve seat.
   Typical fix: Replacement of the left cylinder head assembly. This is a major repair, but was often covered by Chrysler's extended warranty.
   Est. part cost: $500-$1200 for a remanufactured head assembly
4. Faulty Fuel Injector 🟡 Medium Probability
   How to confirm: Use a mechanic's stethoscope to listen for a consistent clicking sound from the injector. You can also test the injector's resistance with a multimeter (a good one should read around 11-12 ohms), or swap it with another cylinder to see if the misfire follows. A P0206 code alongside P0306 strongly points to the injector or its circuit.
   Typical fix: Replace the faulty fuel injector.
   Est. part cost: $70-$150
5. Failed Lifter / Worn Camshaft Lobe (Hemi V8 Engines) 🟡 Medium Probability The 'Hemi tick' is a known issue where the roller on a lifter fails, seizing up and grinding against the camshaft lobe, eventually causing a misfire. This is often attributed to oil breakdown or lack of lubrication during extended idling. The needle bearings in the lifter can disintegrate, leading to catastrophic damage.
   How to confirm: Listen for a distinct ticking or tapping sound from the top of the engine that may get louder as it warms up. A physical inspection by removing the valve covers and potentially the cylinder heads is required for definitive diagnosis. You may see a rocker arm that is not moving as much as the others.
   Typical fix: Replace all lifters on the affected bank and the camshaft. This is a labor-intensive and costly repair. It is often recommended to replace the MDS solenoids at the same time.
   Est. part cost: $800-$2000+ for camshaft and lifter kits

Rare But Worth Checking

• Vacuum Leak: A leak in the intake manifold gasket near cylinder 6 can lean out the air-fuel mixture, causing a misfire. This can be diagnosed with a smoke test.
• Low Compression (Mechanical Engine Damage): Beyond the specific V6 cylinder head issue, a misfire can be caused by other problems like a burnt valve or damaged piston rings. A compression test will identify this.
• Failing Rocker Arms (3.6L Pentastar): Separate from the cylinder head defect, the Pentastar engine can also suffer from rocker arm bearing failure, which creates a ticking noise and can lead to a misfire if the arm seizes or breaks. This can be inspected by removing the valve cover.

Diagnosis Steps

1. Read all stored trouble codes with an OBD-II scanner. Note if any other codes are present, like P0300 or P0206.
2. Identify the location of cylinder 6. On all Challenger engines (V6 and V8), the cylinders are numbered with odd numbers on the passenger side (Bank 1: 1, 3, 5) and even numbers on the driver's side (Bank 2: 2, 4, 6), from front to back. Cylinder 6 is the rearmost cylinder on the driver's side.
3. Swap the ignition coil from cylinder 6 to cylinder 4 (driver's side, middle). Clear the codes and drive the vehicle. If the code changes to P0304, the ignition coil is faulty.
4. If the misfire remains on cylinder 6, inspect and replace the spark plug(s) for that cylinder. Check for proper gap and any signs of fouling.
5. If the issue persists, test the fuel injector. Listen for its operation, check its wiring, and consider swapping it with another cylinder or testing its resistance with a multimeter.
6. If ignition and fuel components are verified as good, a mechanical issue is likely. For Hemi engines, listen carefully for the 'Hemi tick'. For all engines, proceed to a mechanical test.
7. Perform a compression test on cylinder 6. If compression is low, perform a cylinder leak-down test. This is the definitive test for the 3.6L V6 cylinder head issue (leakage >25% is a failure) and can also pinpoint problems like bad rings or valves on any engine.

Parts You'll Likely Need

• Ignition Coil (OEM #68238603AA (Fits many 5.7L/6.4L/6.2L Hemi applications)) — Ignition coils are a common failure point that directly causes a misfire on a single cylinder.
  Trusted brands: Mopar, NGK, Denso
  OEM price range: $50-$90
  Aftermarket price range: $30-$75
• Spark Plug (OEM #SP149125AE (Common for 3.6L V6)) — As a routine maintenance item, spark plugs wear out over time and are a primary cause of misfires.
  Trusted brands: NGK, Champion
  OEM price range: $15-$25
  Aftermarket price range: $5-$15
• Left Cylinder Head Assembly (3.6L V6) (OEM #RL141353AC) — This is the specific fix for the known valve guide and seat issue on 2011-2013 Pentastar engines that triggers P0306.
  Trusted brands: Mopar
  OEM price range: $800-$1500
  Aftermarket price range: $500-$1200 for a remanufactured head assembly

Related Codes That Often Appear With This One

• P0300 — If the misfire is intermittent or affects other cylinders, a general 'Random/Multiple Cylinder Misfire' code may be stored alongside P0306.
• P0206 — This code indicates a fault in the 'Cylinder 6 Injector Circuit'. If you see P0206 with P0306, the problem is almost certainly the fuel injector for cylinder 6 or its wiring.
• P0302, P0304 — On 3.6L V6 engines, seeing these codes along with P0306 strongly points to the known left cylinder head failure, as all three cylinders are on the same bank (Bank 2) and are the specific ones called out in TSB 09-002-14.

Technical Service Bulletins (TSBs) & Recalls

• source — The primary TSB for the 3.6L V6 left cylinder head issue. It applies to 2011-2013 models and outlines the diagnostic procedure: perform a cylinder leak-down test on cylinders 2, 4, and 6. If leakage is 25% or greater, the left cylinder head must be replaced. This repair was covered under the X56 warranty extension (10 years/150,000 miles).
• Not a TSB itself, but a warranty extension program by Chrysler to address the high failure rate of the left cylinder head on 2011-2013 3.6L Pentastar engines. It covered the cost of diagnosis and replacement for 10 years or 150,000 miles from the vehicle's in-service date.

Platform-Specific Known Issues

• 2011-2013 3.6L Pentastar V6 Cylinder Head Defect: These model years are known for a factory defect in the left cylinder head that causes excessive valve guide wear, leading to compression loss and misfires on cylinders 2, 4, and 6. Chrysler issued TSB #09-002-14 REV. B and an extended warranty (X56) for this issue. The repair involves a leak-down test and, if failed, replacement of the entire left cylinder head.
• 5.7L & 6.4L Hemi Lifter/Camshaft Failure: A common issue on Hemi V8 engines is a lifter failure, often preceded by a 'Hemi tick.' The roller bearing on the lifter can fail, destroying the corresponding camshaft lobe. This will eventually cause a persistent misfire on the affected cylinder.

Mechanic-Grade Diagnostic Values

• Fuel Injector Resistance — expected: 11.5 - 12.3 ohms. Failure: A reading of 0 ohms or infinite resistance indicates a failed injector.
• Fuel Pressure at Idle — expected: 44.2 - 54.2 psi. Failure: Pressure significantly below this range could indicate a weak fuel pump, causing lean misfires.

Scan Tool Commands That Help

• wiTECH or advanced generic scanner: Misfire Counter / Live Data — Use this to confirm in real-time that cylinder 6 is the one actively misfiring. A high-end scanner can show misfire counts for each cylinder during a test drive, helping to isolate the issue.
• wiTECH or advanced generic scanner: Injector Kill Test / Bi-Directional Control — This function allows you to manually disable the fuel injector for cylinder 6. If the engine's idle quality does *not* change when cylinder 6 is disabled, it confirms that cylinder was not contributing, strongly pointing to a problem with that specific cylinder's fuel, spark, or compression.

Wiring & Ground Locations

• G104 — Right side of the engine.. This is a primary ground point for multiple engine components, including the Powertrain Control Module (PCM). A loose or corroded ground at this location can cause erratic behavior and phantom codes, including misfires.
• Cylinder 6 Ignition Coil Connector — On the driver's side of the engine (Bank 2), the rearmost coil. The PCM provides a switched ground to control the coil.. This is the final connection for the ignition system on cylinder 6. Testing for power and the ground signal from the PCM at this connector is critical for diagnosing a no-spark condition.
• Cylinder 6 Fuel Injector Connector — Under the intake manifold on the driver's side, rearmost injector. It has a red sliding lock tab that must be disengaged before the connector can be removed.. This connector provides power and the control signal to the fuel injector. Checking for voltage and the pulse signal from the PCM here is necessary if a fuel injector is suspected to be faulty.

Real Owner Repair Stories

• Reddit user redgus78 in /r/MechanicAdvice (2014 Chrysler Town & Country (with the same 3.6L Pentastar V6)) — P0306 code and a rough idle.
  ❌ Tried (didn't work) Swapping ignition coils (misfire stayed on #6), Swapping fuel injectors (misfire stayed on #6), Replacing spark plugs, Performing a compression test (was good), Performing a leak-down test (was good), Confirming spark and injector signals were present
  ✅ What actually fixed it After removing the valve cover for a physical inspection, the problem was identified as a worn exhaust rocker arm and a worn cam lobe on cylinder 6.
• YouTube channel 'Fix It All' (Dodge Challenger with P0300, P0306, and P0206) — Car was shaking, losing power, and had an unstable idle.
  ❌ Tried (didn't work) Initially performed an injector kill test, which showed no change when cylinder 6 was deactivated, confirming the problem was isolated to that cylinder.
  ✅ What actually fixed it The fuel injector for cylinder 6 was faulty. A resistance test showed the old injector had zero ohms (a dead short), while the new, good injector measured 11.6 ohms. Replacing the injector resolved all codes.

OEM Part Supersession History

• RL141353AC (and earlier versions RL141353AA, RL141353AB) → 68141353AC — This part is the left cylinder head for the 3.6L V6, which was redesigned to fix the valve guide and seat issue causing misfires on cylinders 2, 4, and 6 in 2011-2013 models. The newer part numbers represent revised, improved versions.
  Heads up: When replacing the head, a separate bolt/plug kit (Mopar #68154699AA) MUST be used, as the new heads are shipped without oil gallery bolts/plugs. Failure to install this kit will result in trouble codes.

Model Year Variations Within This Range

• 2011-2014 vs 2015-2018: A major refresh occurred in 2015. The most significant mechanical change was the replacement of the old 5-speed automatic transmission (NAG1/WA580) with the much more efficient and faster-shifting ZF 8-speed automatic (8HP series). The exterior and interior were also completely redesigned. While the core engines and their specific flaws (V6 head, Hemi lifters) remained, the transmission change is a major differentiator in performance and fuel economy.
• 2011-2013 (3.6L V6): These specific model years are prone to the left cylinder head failure outlined in TSBs. A P0306 on one of these vehicles has a much higher probability of being this serious mechanical issue compared to a 2014 or newer model.