P0306 on 2011-2014 Chrysler 200 3.6L: Cylinder 6 Misfire Causes and Fixes

What's Unique About the 2011-2014 Chrysler 200

While any car can have a misfire, early 3.6L Pentastar V6 engines used in the 2011-2013 Chrysler 200 are notorious for a specific defect. The left-side cylinder head (which includes cylinder 6) was prone to excessive wear of the valve guides and seats, leading to a loss of compression and persistent misfires. This problem was so widespread that Chrysler issued Technical Service Bulletin 09-002-14 and a 10-year/150,000-mile warranty extension (X56) to cover the cylinder head replacement. The issue was corrected in production starting in mid-2012 with redesigned heads.

Diagnostic Flowchart

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

Symptoms You May Notice

• Flashing or solid Check Engine Light
• Rough or shaking idle, especially on a cold start.
• Engine hesitation or stumbling during acceleration.
• Noticeable loss of engine power.
• Engine stalling
• Smell of fuel from the exhaust
• Audible ticking or tapping noise from the top of the engine, which can indicate rocker arm failure.
• Sloshing sound from behind the dashboard or coolant reservoir filling with exhaust gases, indicating a head gasket leak.

Most Likely Causes

1. Faulty Left Cylinder Head 🔴 High Probability A known manufacturing defect affected the valve seats and guides on the left cylinder head of 2011-2013 3.6L Pentastar engines, causing loss of compression. Cylinders 2, 4, and 6 are on this head. This was addressed by TSB #09-002-14 REV. B. 🎬 Watch: A professional walkthrough of the left cylinder head repair.
   How to confirm: A professional mechanic should perform a cylinder leak-down test. Per TSB 09-002-14, leakage of 25% or greater on cylinder 6 confirms the need for head replacement. Visual inspection of the spark plug may show a reddish/orange color from coolant contamination.
   Typical fix: Replace the left cylinder head with the updated part (e.g., part number starting with RL141353AC or newer). This is a major repair that also requires replacing gaskets for the head, intake plenum, and valve cover.
   Est. part cost: $600-$1200
2. Failed Rocker Arms/Lifters 🔴 High Probability The Pentastar engine is widely known for a 'tick' caused by failing rocker arms. The needle bearings in the rocker arm fail, causing the roller to seize. This scores the camshaft lobe, preventing the valve from opening fully and leading to a misfire. This can happen on any cylinder but is a very common cause for misfires on this engine family.
   How to confirm: After ruling out ignition and fuel, remove the left valve cover and inspect the camshaft lobes and rocker arms for cylinder 6. Look for scoring, wear, or excessive play in the rocker arm roller. A Reddit user with a P0306 on a 2014 T&C confirmed this was the cause after extensive diagnosis.
   Typical fix: Replace all rocker arms and lifters on the affected cylinder head. If the camshaft lobe is scored or damaged, the camshaft must also be replaced. It is highly recommended to replace all 24 rocker arms and lifters as a preventative measure.
   Est. part cost: $150-$400 for rocker arms and lifters; add $200-$500 for a camshaft.
3. Failed Ignition Coil 🟡 Medium Probability Coil-on-plug systems are a common failure point on most modern engines as they age. Heat cycles cause the internal windings to break down.
   How to confirm: Swap the ignition coil from cylinder 6 with another cylinder (e.g., cylinder 4, which is also on the left bank, or cylinder 1 on the easier-to-access right bank). Clear the codes and drive. If the code changes to P0304 or P0301, the coil is bad.
   Typical fix: Replace the faulty ignition coil. It is often recommended to replace all coils on the affected bank, or all six if they are original.
   Est. part cost: $30-$80
4. Worn or Fouled Spark Plug 🟡 Medium Probability Spark plugs are a standard maintenance item with a finite lifespan (typically 100,000 miles). The 3.6L engine requires removing the upper intake manifold to access the rear bank of plugs (2, 4, 6), so replacement of all six is often deferred, leading to misfires.
   How to confirm: Remove the spark plug from cylinder 6 and inspect it. Look for a worn electrode (excessive gap), heavy carbon deposits, oil/fuel fouling, or a cracked insulator. Compare its appearance to plugs from other cylinders.
   Typical fix: Replace the spark plug. It is best practice to replace all six spark plugs at the same time, especially on the 3.6L V6 due to the labor involved. Use OEM-spec Iridium plugs.
   Est. part cost: $10-$25 per plug
5. Clogged or Faulty Fuel Injector ⚪ Low Probability
   How to confirm: A mechanic can perform a fuel injector balance test. A DIY method is to listen to the injector with a mechanic's stethoscope; it should have a consistent, audible clicking sound. You can also swap the injector with another cylinder (similar to the coil swap) to see if the misfire moves.
   Typical fix: Replace the faulty fuel injector.
   Est. part cost: $50-$150

Rare But Worth Checking

• Faulty Crankshaft Position Sensor: Some early Pentastar engines had issues with faulty crankshaft position sensors that could cause intermittent misfire codes across multiple cylinders, including P0306. This is more likely if you also see a P0300 (random misfire) code.
• Vacuum Leak at Intake Manifold Gasket: The upper intake manifold must be removed to service the spark plugs on the rear bank (cylinders 2, 4, 6). If the gasket for cylinder 6's runner is damaged, pinched, or improperly seated during reassembly, it can cause a vacuum leak leading to a lean misfire on that specific cylinder.

Diagnosis Steps

1. Read the trouble codes with an OBD-II scanner to confirm P0306 and any other related codes (e.g., P0300, P0302, P0304).
2. Swap the ignition coil from cylinder 6 with cylinder 4 (or any other cylinder). Clear the codes and drive the vehicle to see if the misfire code moves to the other cylinder (e.g., P0304). If it does, the ignition coil is the problem.
3. If the misfire does not move, inspect the spark plug from cylinder 6. Check for wear, damage, or fouling. Compare it to other plugs. Replace if necessary.
4. If ignition components are good, listen to the fuel injector on cylinder 6 with a stethoscope to ensure it is clicking consistently. Consider swapping the injector if you have the tools and skill.
5. If the vehicle is a 2011-2013 model, the next step is to suspect the cylinder head. The vehicle should be taken to a professional for a cylinder leak-down test. A result of 25% or more leakage confirms a mechanical engine problem, likely the head, as per TSB 09-002-14.
6. For all model years, if a ticking noise is present and ignition/fuel issues are ruled out, remove the valve cover to inspect the rocker arms and camshaft lobes for cylinder 6 for visible wear or damage.

Parts You'll Likely Need

• Left Cylinder Head Assembly (OEM #RL141353AC (superseded part)) — This is the primary fix for the known manufacturing defect on 2011-2013 models that causes P0306. The replacement part has been updated to correct the flaw. The original failing part may be 05184445AI.
  Trusted brands: Mopar
  OEM price range: $800-$1200
  Aftermarket price range: $600-$900
• Rocker Arm (Cam Follower) — A very common failure point on the 3.6L Pentastar leading to misfires. The bearing seizes, damaging the camshaft.

Related Codes That Often Appear With This One

• P0300 — This code means 'Random/Multiple Cylinder Misfire Detected'. It often appears with P0306 if the misfire is intermittent or affecting other cylinders, which is common with both the cylinder head and rocker arm issues.
• P0302 / P0304 — These codes indicate misfires on cylinders 2 and 4. Since all three cylinders (2, 4, 6) are on the same left-side cylinder head, seeing these codes together strongly points to the common cylinder head failure.
• P0206 — This code indicates a fault in the 'Cylinder 6 Injector Circuit'. It can appear alongside P0306 if the PCM detects an issue with the injector itself or its wiring, or if the PCM intentionally shuts down the injector in response to the persistent misfire.

Technical Service Bulletins (TSBs) & Recalls

• Bulletin #09-002-14 Rev. B: 'MIL Illumination: P0300, P0302, P0304 or P0306 (X56 Warranty Extension)' - This bulletin details checking for cylinder leakage of 25% or more and replacing the left cylinder head if necessary. It lists all affected vehicles, including the Chrysler 200/Avenger.
• Bulletin #1810216: Confirms the definition of P0306 as 'Cylinder 6 Misfire' among a list of other diagnostic trouble codes.
• Warranty Bulletin D-14-12: This document officially outlines the 10-year/150,000-mile warranty extension for the left cylinder head and references TSB 09-002-14 for the repair procedure.

Platform-Specific Known Issues

• Extended Warranty (X56) for Left Cylinder Head: Chrysler acknowledged a defect in the left cylinder head on 2011-2013 models equipped with the 3.6L engine. This defect caused misfire codes P0300, P0302, P0304, and P0306. The warranty was extended to 10 years or 150,000 miles. While this period has likely expired for most vehicles, its existence confirms the high failure rate of this part. Customers who paid for this repair out-of-pocket could apply for reimbursement.
• Rocker Arm / Cam Follower Failure: A widespread issue across all applications of the 3.6L Pentastar is the failure of the rocker arm bearings. This typically starts as a ticking sound and can progress to a misfire code like P0306 and eventually cause camshaft damage. The repair involves replacing the rocker arms and potentially the camshafts, which is labor-intensive.

Mechanic-Grade Diagnostic Values

• Cylinder Leak-Down Test (on Cylinders 2, 4, or 6) — expected: Less than 25% leakage. Failure: Leakage of 25% or greater
• Fuel Pressure at Idle — expected: 55-65 psi. Failure: Pressure significantly below 55 psi, especially under load.
• Total Fuel Trim (Short Term + Long Term) — expected: Between -10% and +10%. Failure: Values consistently exceeding +/-10% indicate a potential vacuum leak, fuel delivery issue, or sensor problem that could contribute to a misfire.

Scan Tool Commands That Help

• wiTECH (Chrysler Dealer Tool): View Live Misfire Counts — Navigate to PCM > Monitors > OBD II Monitors and select 'Which cylinder is misfiring'. This provides real-time counts for each cylinder, helping to confirm the misfire is isolated to cylinder 6 and to diagnose intermittent issues under specific load conditions.
• Professional Scan Tool (e.g., wiTECH): Actuate ASD Relay — To diagnose a no-spark condition. A technician can command the Auto Shutdown (ASD) relay on and then use a multimeter to check for voltage at the (F142) ASD Relay Output circuit in the ignition coil harness connector, confirming power delivery to the coils.

Wiring & Ground Locations

• Cylinder 6 Ignition Coil — On top of the left valve cover (the bank closer to the firewall), in the rearmost position.. This is the physical component responsible for firing the spark plug for cylinder 6. Access requires removing the upper intake manifold.
• Cylinder 6 Coil Control Circuit — The circuit is designated (K10) and is located in the C2 PCM harness connector.. This is the specific wire from the Powertrain Control Module (PCM) that sends the signal to fire the cylinder 6 ignition coil. A break or short in this wire will cause a P0306.
• G302 Ground — Located at the left kick panel inside the vehicle cabin.. While not exclusively for the ignition system, poor grounds in this area can cause a variety of difficult-to-diagnose electrical issues for engine management components.

Real Owner Repair Stories

• Reddit user 'redgus78' in r/MechanicAdvice (2014 Chrysler Town & Country with 3.6L Pentastar) — P0306 code and a rough idle.
  ❌ Tried (didn't work) Swapping ignition coils (misfire stayed on cylinder 6), Swapping fuel injectors (misfire stayed on cylinder 6), Replacing spark plugs, Performing a compression check (was good and consistent), Performing a leak-down test (was good)
  ✅ What actually fixed it A worn exhaust rocker arm and a scored cam lobe on cylinder 6 were found after removing the valve cover. Replacing the affected rocker arm and camshaft resolved the P0306 code.

"I Checked Everything" — The Actual Cause

• In cases where ignition parts, fuel injectors, and vacuum leak tests (like a smoke test) all check out, the root cause is frequently mechanical. For the 3.6L Pentastar, this often points to a failed rocker arm bearing, which seizes and scores the camshaft lobe. This prevents the valve from opening correctly, causing a misfire that standard electronic and fuel system diagnostics will miss.

OEM Part Supersession History

• 05184445AI (and others) → RL141353AC (remanufactured) or 68141353AC (new) — To correct a design flaw causing premature valve guide and seat wear on the left cylinder head of 2011-2013 engines.
  Heads up: When replacing the head with the updated part, a separate bolt/plug kit (Mopar #68154699AA) MUST be used, as the new heads are shipped without the necessary oil gallery bolts and plugs. Failure to install this kit will lead to other engine problems.
• Various → N/A — Part design difference.
  Heads up: Pentastar engines use either a 2-wire or 3-wire ignition coil depending on the model year and vehicle. The 2011-2014 Chrysler 200 uses a 2-wire coil. Using a 3-wire coil from a different application will not work.

Model Year Variations Within This Range

• 2011-2013: These model years are susceptible to the left cylinder head failure. The problem was addressed in production starting in the summer of 2012. Replacement heads should have a casting date of '2062' (206th day of 2012) or later to ensure they are the corrected design. 2014 models have the updated cylinder head from the factory and are not prone to this specific issue, making rocker arm failure a more likely mechanical cause.