P0306 on 2024 Chevrolet Traverse: Cylinder 6 Misfire Causes and Fixes

What's Unique About the 2024-2024 Chevrolet Traverse

The 2024 Chevrolet Traverse introduces an all-new 2.5L Turbocharged Inline-4 engine (RPO code: LK0), which replaces the previous 3.6L V6. 🎬 Watch: A deep dive into the new 2.5L LK0 engine. This engine is a smaller version of the 2.7L L3B found in GM trucks and features direct injection and Dynamic Fuel Management (cylinder deactivation), which can complicate diagnostics. Because this powertrain is brand new, there are no established long-term failure patterns. Any P0306 code on a vehicle this new is almost certainly due to a premature part failure or manufacturing defect. All diagnostic and repair work must be performed by a dealer to maintain the factory warranty and to check for any preliminary service bulletins related to the new engine.

Symptoms You May Notice

• Flashing or solid Check Engine Light
• Rough engine idle or shaking/vibrating
• Noticeable loss of power and acceleration
• Hesitation or stumbling when trying to accelerate
• Reduced fuel economy
• Engine may make popping or backfiring sounds
🎬 See this breakdown of common P0306 causes and fixes.

Most Likely Causes

1. Faulty Ignition Coil 🔴 High Probability → Shop Ignition Coil On a new vehicle, an early failure of an electronic component like an ignition coil is a primary suspect for a single-cylinder misfire. ACDelco coils use pure copper windings, but manufacturing defects can still occur.
   How to confirm: A technician will swap the cylinder 6 ignition coil with another cylinder's coil (e.g., cylinder 1). If the misfire code changes to P0301, the coil is confirmed as the faulty part.
   Typical fix: Replacement of the faulty ignition coil. This is a warranty repair.
   Est. part cost: $0 (Warranty)
2. Defective Spark Plug 🟡 Medium Probability → Shop Spark Plug Though modern iridium spark plugs are durable, a manufacturing defect (like a cracked insulator) can cause a misfire from day one.
   How to confirm: After ruling out the coil, a technician will inspect the spark plug for damage, fouling, or an incorrect gap. They may swap it with another cylinder's plug to see if the misfire follows.
   Typical fix: Replacement of the defective spark plug. This is a warranty repair.
   Est. part cost: $0 (Warranty)
3. Faulty Fuel Injector ⚪ Low Probability → Shop Fuel Injector The LK0 engine uses direct injection, and a manufacturing issue with the fuel injector for cylinder 6 could cause it to deliver an incorrect fuel spray pattern, leading to a misfire. GM has issued bulletins for other new models regarding injector testing for similar issues.
   How to confirm: This is a more complex diagnosis involving checking fuel trims and performing an injector balance test with a GM-specific scan tool. This should only be done by a qualified technician.
   Typical fix: Replacement of the faulty fuel injector. This is a warranty repair.
   Est. part cost: $0 (Warranty)
4. Wiring or Connector Issue ⚪ Low Probability A loose pin in a connector, a loose ignition coil ground bolt, or a damaged wire in the harness leading to the coil or injector for cylinder 6 can cause an intermittent or constant misfire.
   How to confirm: A technician will perform a visual inspection and a continuity (wiggle) test on the wiring harness for cylinder 6.
   Typical fix: Repairing the affected wiring or connector. This is a warranty repair.
   Est. part cost: $0 (Warranty)

Rare But Worth Checking

• Internal Engine Mechanical Failure:
• Carbon Buildup on Intake Valves:

Diagnosis Steps

1. Confirm the vehicle is under warranty. If so, stop and schedule an appointment with a Chevrolet dealership. The following steps are for informational purposes on what the dealer will do.
2. Use a professional OBD-II scanner (like a GM GDS2) to confirm the P0306 code and check for any other codes or relevant manufacturer-specific bulletins.
3. Note the freeze-frame data to understand the engine conditions (RPM, load, temperature) when the misfire occurred.
4. Check the live data on the scanner to monitor misfire counts for cylinder 6 in real-time.
5. Swap the ignition coil from cylinder 6 with another cylinder (e.g., cylinder 2). Clear the codes and run the engine. If the code changes to P0302, the ignition coil is the problem.
6. If the code remains P0306, swap the spark plug from cylinder 6 with another cylinder. If the code follows the plug, the spark plug is the problem.
🎬 Watch: How to diagnose and repair cylinder 6 misfire codes.
7. If the misfire still remains on cylinder 6, the technician will inspect the wiring and connector to the coil and injector for cylinder 6.
8. If wiring is good, the next step is to test the fuel injector, likely with an injector balance test.
9. If all else fails, a mechanical issue is suspected, and a compression test will be performed.

Parts You'll Likely Need

• Ignition Coil (OEM #12696103) — An ignition coil is the most likely electronic component to fail prematurely and cause a single-cylinder misfire.
  Trusted brands: ACDelco
  OEM price range: $0 (Warranty)
  Aftermarket price range: $40-$80
• Spark Plug (OEM #12698807) — A spark plug with a manufacturing defect can cause a misfire, and it's the second part to check after the coil.
  Trusted brands: ACDelco Iridium
  OEM price range: $0 (Warranty)
  Aftermarket price range: $15-$25

Related Codes That Often Appear With This One

• P0300 — If the condition causing the misfire on cylinder 6 is intermittent or begins to affect other cylinders, a P0300 (Random/Multiple Cylinder Misfire) code may also be stored.

Technical Service Bulletins (TSBs) & Recalls

• PIP6102: Preliminary information regarding an investigation into unexpected engine stalling on 2024-2026 models with the 2.5L LK0 engine.
• Bulletin #PIP5038B: Notes that vehicles may have a Service Engine Soon Malfunction Indicator Lamp on with Diagnostic Trouble Codes including P0306 and P0356, requiring technicians to follow published Service Information diagnostics.

Mechanic-Grade Diagnostic Values

• Ignition Coil Primary Winding Resistance — expected: 0.4 - 2.0 Ohms. Failure: A reading of 0 ohms (short) or OL/infinite (open circuit).
• Ignition Coil Secondary Winding Resistance — expected: 6,000 - 11,000 Ohms (6kΩ - 11kΩ). Failure: A reading significantly outside this range.
• GDS2 Fuel Injector Balance Test — expected: The pressure drop for each injector should be within 20 kPa (3 psi) of the average pressure drop for all cylinders.. Failure: A cylinder's pressure drop falling outside the specified range indicates a faulty injector.

Hidden / Shadow Codes Worth Checking

• Mode $06 Misfire Data (e.g., OBDMID $A2-$A7): Mode $06 data allows a technician to view raw misfire counts per cylinder for the current and previous 10 driving cycles. This can identify a cylinder that is misfiring intermittently but not frequently enough to trigger a P030x code and turn on the check engine light. It's a key tool for diagnosing intermittent issues. (see via A professional OBD-II scanner with Mode $06 capability. Note that on some GM vehicles, the cylinder data can be misaligned (e.g., OBDMID $A3 might report on cylinder #3 instead of #2), so consulting service information for the specific Test ID is crucial.)

Scan Tool Commands That Help

• GM GDS2 / Tech2: Misfire Counts — This live data PID shows real-time misfires on each cylinder, which is the primary method to verify the P0306 is active and to confirm a repair by seeing the counts on cylinder 6 drop to zero.
• GM GDS2 with AFIT Tool: AFIT (Active Fuel Injector Test) — After ruling out spark, this is the definitive test for a faulty fuel injector. It measures pressure drop to identify leaking or clogged injectors without removal. Per TSB PIP5993A, this is a required diagnostic step. CRITICAL NOTE: The G10 AFIT adapter will NOT work for a fuel injector balance test on this engine; it will always read zero. The updated G11 adapter is required due to a production change in the fuel pressure sensor.

Wiring & Ground Locations

• Connector X160 — Engine harness connector, specific location requires service manual diagram.. GM Service Bulletin PIP5993A specifically calls out checking terminal tension at connector X160 when diagnosing misfires on the LK0 engine. Another bulletin for related engines notes this connector is a common point for poor terminal tension affecting fuel injectors.
• Engine Harness Chafe Points — General areas to inspect include where the harness passes over the camshaft carrier cover, near the ECM mounting bracket, and around the air cleaner housing.. While not specific to the Traverse, GM TSBs for other recent models with similar engine layouts highlight these as common areas where engine vibration can cause the harness to rub through, shorting wires for coils or injectors and causing misfires.
• Ignition Coil Ground — Typically located on the rear of the cylinder head. GM uses a 'G###' naming convention (e.g., G102).. A loose or corroded ground for the ignition coils can cause a weak spark and lead to single or multiple cylinder misfires. While the specific ground number for the LK0 is not yet widely published, checking the main engine-to-chassis and cylinder head grounds is a key step for any electrical issue.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Unexpected Engine Stalling 🔴 High — Affects 2024-2026 models with the 2.5L LK0 engine. May occur after a remote start or when selecting Drive/Reverse, especially in cold weather. Root cause is under investigation by GM. (Ref: PIP6102)
• Transmission Failures and Malfunctions 🔴 High — Owners report a range of issues including complete transmission failure, hard shifting, and sudden deceleration. (Ref: 20-NA-136 (Pilot Program for transmission replacement))
• Braking System Malfunctions 🔴 High — Complaints include brake assist warnings, stiff brake pedals making the vehicle difficult to stop, and phantom braking events where the car stops unexpectedly.
• Driver-Assist & Electrical System Glitches 🟠 Medium — Owners report non-functional Super Cruise/adaptive cruise control, phantom collision warnings, and faulty brake pad wear sensors causing incorrect warnings. (Ref: PIT6167C (Super Cruise inoperative), 24-NA-193 (Radio software issues))
• Coolant Leaks 🟠 Medium — Some owners have reported coolant leaks, traced back to issues like a cracked radiator hose from factory installation or a faulty coolant reservoir.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: For a 2024 model year vehicle, using a used part from a junkyard for a powertrain-related fault like a P0306 is never a smart choice. The vehicle is covered by the manufacturer's bumper-to-bumper and powertrain warranties, which will cover the diagnosis and repair at no cost to the owner.

What to inspect on the donor part:

• Not applicable. Do not use donor parts while the vehicle is under warranty.

OEM-only on this vehicle (don't cheap out):

• Ignition Coil
• Spark Plug
• Fuel Injector
• Engine Control Module (ECM)
• Any internal engine component

Aftermarket brands forum-validated for this vehicle:

• None at this time. The powertrain is too new for the aftermarket to have established a reputation for quality and reliability. Only OEM (ACDelco) parts installed by a dealer should be used.

Brands owners have reported issues with on this vehicle:

• All non-OEM brands should be avoided for this vehicle and fault code until the aftermarket has had years to prove compatibility and durability with the new LK0 engine platform.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0301 — This code appears if a technician swaps the ignition coil from cylinder 6 to cylinder 1 to confirm the coil is the faulty component.
• P0302 — This code appears during the diagnostic process if the cylinder 6 ignition coil is moved to cylinder 2 to verify a component failure.
• PIP6102 — Manufacturer reference for unexpected engine stalling investigations involving the same 2.5L LK0 engine platform.
• 20-NA-136 — Technical bulletin reference for transmission failures which may occur alongside powertrain codes on this platform.
• PIT6167C — Related to electrical system glitches and Super Cruise inoperative warnings frequently reported by owners of this vehicle generation.

Frequently Asked Questions