P0307 on 2010-2015 Chevrolet Camaro 6.2L V8: Cylinder 7 Misfire Causes and Fixes

What's Unique About the 2010-2015 Chevrolet Camaro

The 5th Gen Camaro V8 has two key vulnerabilities for this code. First, the spark plug wire for cylinder #7 is routed in a high-heat area near the exhaust manifold, making it prone to damage, a problem noted in service bulletins and by owners, especially after installing aftermarket headers. Second, the L99 engine in automatic-equipped cars uses Active Fuel Management (AFM), which deactivates cylinder 7 under light loads. The AFM lifters for these cylinders are a known weak point and a frequent cause of persistent misfires that can become stuck or collapse.

Symptoms You May Notice

• Rough idle or shaking, especially at a stop
• Engine hesitation or stumbling during acceleration
• Noticeable loss of power
• Flashing Check Engine Light (indicates a severe misfire)
• Engine running rough
• Ticking or tapping noise from the engine (can indicate a lifter issue on L99 models)

Most Likely Causes

1. Damaged or Loose Spark Plug Wire 🔴 High Probability → Shop Spark Plug Cylinder 7 is the rearmost on the driver's side, and its wire is exposed to high heat from the exhaust manifold, causing it to degrade, melt, or arc. TSB PIP4819A specifically notes this issue, often related to loose connections. The problem is very common after installing aftermarket headers which can get closer to the wire. Forum users on Camaro5.com frequently cite a melted #7 plug wire as the first thing to check.
   How to confirm: Visually inspect the spark plug wire for cylinder 7 for cracks, melting, or white ash (arcing). Ensure it's securely clicked onto the spark plug and coil. At night, you may be able to see a spark jumping from the wire to the engine block. A broken wire inside the insulation can also be the cause.
   Typical fix: Replace the spark plug wire. It is best practice to replace all 8 wires as a set. 🎬 Watch: How to safely replace LS3 spark plugs and wires. Many owners install high-temperature wire sleeves (often called 'plug wire socks') or metal heat shields on the #7 wire boot for added protection.
   Est. part cost: $50-$150
2. Failed AFM Lifter (L99 Engine Only) 🔴 High Probability → Shop Engine Valve Lifter The L99 engine (automatics) uses Active Fuel Management (AFM) which deactivates cylinders 1, 4, 6, and 7. The hydraulic lifters used for this system are a known major failure point, frequently getting stuck or collapsing, causing a permanent misfire on the affected cylinder. The issue was common enough that GM released an updated lifter design, but cars as late as 2013 were still built with the older, failure-prone parts.
   How to confirm: After ruling out ignition and fuel issues, this is the next logical step. A key symptom is a persistent ticking noise from the engine that may be intermittent on startup. A mechanic can confirm by removing the valve cover and observing if the rocker arms for cylinder 7 are moving properly while the engine is running. A compression test will also show very low or zero compression if the lifter is collapsed.
   Typical fix: This is a major repair requiring removal of the cylinder head to replace the failed lifter(s). Many owners opt to perform an 'AFM Delete', replacing all AFM components (lifters, camshaft, valley cover) with standard LS3 parts and reprogramming the ECU to prevent future failures. This is often done as part of a performance camshaft upgrade. 🎬 See this walkthrough on replacing and disabling failed AFM lifters.
   Est. part cost: $200-$800
3. Worn or Fouled Spark Plug 🟡 Medium Probability → Shop Spark Plug
   How to confirm: Remove the spark plug from cylinder 7 and inspect it. Look for a worn electrode, heavy carbon buildup, or oil fouling. Compare it to a plug from a different cylinder. The easiest test is to swap the cylinder 7 plug with another (e.g., cylinder 5) and see if the code changes to P0305.
   Typical fix: Replace the spark plug. It's recommended to replace all 8 plugs at the same time. The OEM ACDelco Iridium plug is part number 41-110.
   Est. part cost: $8-$20 per plug
4. Defective Ignition Coil 🟡 Medium Probability → Shop Ignition Coil
   How to confirm: Swap the ignition coil from cylinder 7 with another cylinder (e.g., cylinder 5). Clear the codes with a scanner and drive the vehicle. If the trouble code changes to P0305, the ignition coil is faulty.
   Typical fix: Replace the faulty ignition coil. The OEM part number is often 12611424.
   Est. part cost: $40-$90
5. Faulty Fuel Injector ⚪ Low Probability → Shop Fuel Injector
   How to confirm: Use a mechanic's stethoscope or a long screwdriver to listen to the injector on cylinder 7. It should have a consistent, audible clicking sound. You can also use a 'noid light' to confirm the electrical pulse is reaching the injector. Swapping injectors is a definitive but more labor-intensive test.
   Typical fix: Replace the faulty fuel injector.
   Est. part cost: $50-$120

Rare But Worth Checking

• Broken Valve Spring: While not extremely common, valve springs are a known weak point on some LS-family engines. This will cause a sudden, severe misfire and requires a compression test to diagnose. One owner of a 2010 Camaro SS experienced this, though it was on cylinder #8.
• Intake Manifold Gasket Leak: → Shop Engine Intake Manifold A vacuum leak near the intake port for cylinder 7 can lean out the air/fuel mixture and cause a misfire. This would typically be accompanied by a P0171 or P0174 lean code.
• Damaged Coil Pack Connector/Wiring: → Shop Ignition Coil Similar to the spark plug wire, the wiring and plastic connector for the ignition coil can become brittle and break from heat cycles, causing an intermittent connection. One owner on CorvetteForum with an LS2 engine found a broken wire at the connector was the cause of their P0307 and P0357 codes.

Diagnosis Steps

1. Read the code with an OBD-II scanner and check for any other codes. Note the freeze-frame data to see when the misfire occurred.
2. Visually inspect the spark plug wire for cylinder 7 (rearmost on driver's side). Look for any signs of melting, cracking, or looseness. Pay close attention to the boot near the exhaust manifold.
3. Swap the ignition coil from cylinder 7 with cylinder 5 (the one in front of it). Also inspect the coil's electrical connector for damage. Clear the codes and drive. If the code changes to P0305, the coil is bad.
4. If the code remains P0307, swap the spark plugs between cylinders 7 and 5. Clear the codes and drive. If the code changes to P0305, the spark plug is bad.
🎬 Watch: Two quick DIY methods to diagnose a P0307 code.
5. If the misfire is still on cylinder 7, check the fuel system. Listen for the click of the fuel injector on cylinder 7. Use a noid light to verify it's receiving an electrical signal.
6. If ignition and fuel signal are confirmed, a mechanical issue is likely. Perform a compression test on cylinder 7. Low compression points to an internal engine problem.
7. For L99 (automatic) models: If compression is low and/or a ticking noise is present, suspect a failed AFM lifter. This can be confirmed by removing the valve cover and observing the valve train for lack of movement on cylinder 7's rockers.

Parts You'll Likely Need

• Spark Plug Wire Set — The wire for cylinder 7 is highly prone to heat damage from the exhaust manifold. It's best to replace them as a set.
  Trusted brands: ACDelco, NGK, MSD
  OEM price range: $70-$120
  Aftermarket price range: $50-$150
• Ignition Coil (OEM #12611424) — A common failure point for any vehicle, causing a lack of spark.
  Trusted brands: ACDelco, Delphi, Denso
  OEM price range: $60-$90
  Aftermarket price range: $40-$70
• Spark Plug (OEM #41-110) — Spark plugs are a routine maintenance item and can become worn or fouled, causing a weak or non-existent spark.
  Trusted brands: ACDelco, NGK
  OEM price range: $10-$15
  Aftermarket price range: $8-$12
• AFM Valve Lifter Kit (L99 Engine) (OEM #12698946 (Single Lifter)) — A very common mechanical failure on the L99 engine with Active Fuel Management. Cylinder 7 is an AFM cylinder. A failed lifter will cause a persistent misfire. Kits often include lifters and new guide trays.
  Trusted brands: ACDelco, General Motors, Michigan Motorsports
  OEM price range: $200-$400
  Aftermarket price range: $150-$300

Related Codes That Often Appear With This One

• P0300 — If the misfire is intermittent or starting to affect other cylinders, a P0300 (Random/Multiple Cylinder Misfire) may appear. This can happen with a failing AFM lifter that is beginning to affect other AFM cylinders.
• P0357 — This code means 'Ignition Coil 'G' Primary/Secondary Circuit Malfunction', where 'G' corresponds to cylinder 7. It often appears with P0307 and points directly to a problem with the ignition coil itself or its wiring/connector.

Technical Service Bulletins (TSBs) & Recalls

• PIP4819A: Notes that a loose connection at the spark plug can cause a misfire code. While not specific to heat damage, it's a known issue for this cylinder.
• PIC5984: Addresses a gurgle/hiss noise from the dash area, which can be caused by a clogged heater core inlet screen. While not a P0307 cause, it's relevant to dash-area noises.

Platform-Specific Known Issues

• AFM Lifter Failure (L99): → Shop Engine Valve Lifter The most significant issue for L99-equipped automatic Camaros. The Active Fuel Management lifters, particularly on cylinder 7, are prone to collapsing or sticking. This is a well-documented issue across many GM vehicles with this technology.
• Cylinder 7 Spark Plug Wire Heat Damage: → Shop Spark Plug The routing of the #7 spark plug wire near the exhaust manifold makes it highly susceptible to melting and arcing, a problem exacerbated by aftermarket headers.

Mechanic-Grade Diagnostic Values

• Fuel Pressure (Key ON, Engine OFF) — expected: 58 psi (400 kPa). The pressure is controlled by the Fuel Pump Control Module (FPCM) and may be commanded to drop to ~50 psi at higher RPMs on a stock SS tune.. Failure: Pressure below 41 psi may indicate a weak fuel pump or faulty regulator.
• Stock Fuel Injector Resistance — expected: Around 12 Ohms (High Impedance).. Failure: A reading significantly higher or lower than 12 Ohms, or an open circuit, indicates a failed injector coil.
• Ignition Coil Secondary Resistance — expected: 5,000 to 7,200 Ohms (5.0-7.2 kOhms).. Failure: A reading outside of this range suggests the coil's secondary winding is faulty.
• Ignition Coil Primary Resistance — expected: 0.4 to 0.6 Ohms.. Failure: A reading outside this very low range indicates a fault in the primary winding.

Hidden / Shadow Codes Worth Checking

• Mode 6, Test ID $A2-$AF, Component ID $01-$0C: This data tracks the raw misfire count for each cylinder over the last 10 driving cycles. Even if P0307 isn't currently active, checking the count for cylinder 7 (Test ID $A8) can reveal an intermittent issue before it's severe enough to trigger the check engine light. (see via A professional scan tool capable of viewing Mode 6 data, such as a GM GDS2/Tech2 or high-end consumer models.)

Scan Tool Commands That Help

• GDS2 / Tech2: Cylinder Power Balance Test — This is a crucial bidirectional test to confirm a misfire on a specific cylinder. The tool commands the ECM to cut fuel to each injector one by one. When a healthy cylinder is deactivated, there should be a clear drop in RPM. If deactivating cylinder 7 causes little or no change in RPM, it confirms that cylinder is not contributing power, pointing to a spark, fuel, or mechanical fault on that cylinder.

Wiring & Ground Locations

• G102 — At the left rear of the engine (driver's side).. This is the primary ground point for all 8 ignition coils. A loose or corroded connection here can cause weak or intermittent spark on any cylinder, including cylinder 7.
• G106 / G107 — G106 is on the right side of the engine block for the 6.2L V8. G107 is on the left rear of the engine.. These are major engine-to-chassis grounds. The ignition coils ground through the cylinder heads to the block, which relies on these straps for a clean path to the battery negative. A poor connection at G107 on the driver's side can specifically impact the bank containing cylinder 7.
• Cylinder 7 Fuel Injector Wiring — Connector at the fuel injector on the rearmost driver's side cylinder.. The control wire from the ECM for injector 7 is typically an Orange/Black wire at pin 40 of the X1 ECM connector. The power feed is a Pink wire, common to all injectors on that bank. Damage to the Orange/Black wire will prevent the injector from firing.

Real Owner Repair Stories

• Camaro5 forum user (2012 Chevrolet Camaro, 28k miles) — Check Engine Light with code P0307, appeared 5 months after installing aftermarket headers.
  ❌ Tried (didn't work) Initial scan only showed the code.
  ✅ What actually fixed it The issue was an improperly seated spark plug wire on cylinder 7. The wire was not fully clicked onto the spark plug or ignition coil after the header installation, causing a poor connection and misfire.

OEM Part Supersession History

• HL-7011 (AFM Lifter) → HL-7025 — The HL-7025 is a newer 2022 design created for the more complex Dynamic Fuel Management (DFM) systems but is fully backward-compatible with older AFM systems.
  Heads up: The new DFM lifter (HL-7025) works in older AFM engines, but the original AFM lifter (HL-7011) will NOT work in newer DFM engines.

Model Year Variations Within This Range

• 2010-2013 (L99): Earlier model year L99 engines were more susceptible to the AFM lifter failure. While GM made revisions, a class-action lawsuit suggests that lifter issues persist in vehicles up to the 2014 model year and beyond in other GM applications, indicating the problem was not fully resolved within this generation.

Diagnostic Flowchart

Other Known Issues on This Vehicle

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

• AFM Lifter Failure (L99 Engine) 🔴 High → Shop Engine Valve Lifter — Common on L99 engines, especially over 60,000 miles. Can happen earlier. (Ref: Multiple TSBs exist regarding AFM noise and lifter replacement.)
• Heater Core Failure / Clogged Inlet 🟠 Medium — A known issue where the heater core leaks or the inlet screen clogs, causing gurgling noises or coolant leaks on the passenger floor. Repair is extremely labor-intensive, requiring dashboard removal. (Ref: TSB PIC5984 addresses cleaning the inlet screen.)
• Rear Differential Whine/Groan 🟡 Low — Many owners report a groaning noise from the limited-slip differential during slow, tight turns, or a whine at cruising speed. Often resolved by changing the fluid and adding the correct friction modifier. (Ref: A TSB exists for the low-speed groan, recommending a fluid change.)
• Ignition Key/Switch Recall 🔴 High — A major recall (GM Recall No. 14294) was issued because the driver's knee could bump the key fob, causing the engine to shut off while driving. (Ref: NHTSA Campaign ID: 14V346000)
• Premature Timing Chain Wear (V6 Models) 🔴 High — Primarily affects the LLT V6 engine (2010-2011), not the V8s. Stretching timing chains would cause P0008/P0017 codes and require a major engine repair. (Ref: TSB 12-06-01-009G)
• Rear Axle Click / Wheel Bearing Noise 🟡 Low — Some owners experience a clicking noise from the rear axle area, which can be due to a faulty wheel bearing/hub assembly or require a new axle washer per a TSB. (Ref: TSB exists for axle washer replacement on early models.)

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: Used parts can be a cost-effective choice for ignition coils and potentially the engine wiring harness if it's in good condition. These parts are generally robust and their condition can be visually assessed.

Donor-vehicle mileage cap: roughly under 75000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For ignition coils, check for cracks in the plastic housing and corrosion on the electrical pins and spark plug tower.
• For a wiring harness, inspect for brittle plastic connectors, cut wires, or amateurish-looking splices. Ensure all connector locks are intact.
• Avoid parts from vehicles that show signs of flood damage or major front-end collisions.

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

• AFM Lifters: This is a critical failure point. Aftermarket lifters have a mixed reputation. Given the extensive labor involved, using new OEM (or OEM-quality like Elgin) lifters is the only recommended path to ensure a lasting repair. Never install used lifters.

Aftermarket brands forum-validated for this vehicle:

• Ignition Coils: Delphi, Denso, ACDelco (OEM)
• Spark Plugs: NGK, ACDelco (OEM)
• Spark Plug Wires: MSD, NGK, ACDelco (OEM)
• AFM Lifters / Delete Kits: Texas Speed, Brian Tooley Racing (BTR), Michigan Motorsports, Elgin.

Brands owners have reported issues with on this vehicle:

• Unnamed, no-brand ignition coils and sensors from online marketplaces are frequently reported to fail prematurely.

Real Owner Stories

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

Related OBD-II Codes

• P0300 — A random or multiple cylinder misfire code that often appears alongside P0307, especially during the diagnostic phase of AFM lifter failure.
• P0305 — A diagnostic companion code; if the P0307 code moves to P0305 after swapping the coil or spark plug from cylinder 7 to cylinder 5, it confirms the swapped component is faulty.
• P0301 — Another AFM-related cylinder misfire; the L99 engine deactivates cylinders 1, 4, 6, and 7, making these cylinders prone to similar lifter-related failures.
• P0304 — A misfire code for a cylinder (4) that is also part of the Active Fuel Management (AFM) system, sharing the same failure-prone lifter architecture as cylinder 7.
• P0306 — A misfire code for a cylinder (6) that is also part of the Active Fuel Management (AFM) system, sharing the same failure-prone lifter architecture as cylinder 7.

Frequently Asked Questions