P0302 on 2010-2017 Chevrolet Silverado 1500: Cylinder 2 Misfire Causes and Fixes

What's Unique About the 2010-2017 Chevrolet SILVERADO 1500

This year range covers two Silverado generations (GMT900 and K2XX) which both feature V8 engines with Active Fuel Management (AFM). This system deactivates cylinders to save fuel but is a known weak point, with AFM lifters prone to failure, causing misfires. The lifters can get stuck, collapse, or damage the camshaft, leading to persistent misfires and costly repairs. This issue is so prevalent that it has resulted in class-action lawsuits against GM. A GM Technical Service Bulletin (TSB PIP4819A) also specifically notes that loose spark plug wires can cause this code. Another TSB (15-06-01-002H) directly addresses AFM lifter failure as a cause for misfires.

Diagnostic Flowchart

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

Generation note: This range covers the end of the 2nd generation (2010-2013 GMT900) and the start of the 3rd generation (2014-2017 K2XX). Both generations used V8 engines with Active Fuel Management (AFM), which is a primary source of vehicle-specific issues. The 2014+ models feature direct injection EcoTec3 engines, which can have different fuel injector failure modes and are susceptible to carbon buildup on intake valves, which can also cause misfires.

Symptoms You May Notice

• Rough or shaking idle
• Hesitation or stumbling during acceleration
• Flashing or solid Check Engine Light
• Reduced engine power
• Increased fuel consumption
• Engine ticking or tapping noise, especially from the passenger side valve cover area (can indicate a lifter issue)
• Exhaust smell of raw gasoline

Most Likely Causes

1. Worn or Fouled Spark Plug 🔴 High Probability Spark plugs are a regular maintenance item. Oil consumption, sometimes related to the PCV system or AFM operation, can foul plugs prematurely. The recommended OEM plug is often an ACDelco Iridium type.
   How to confirm: Remove the spark plug from cylinder 2 and inspect it for wear, damage, or fouling from oil or carbon. Compare it to a plug from another cylinder.
   Typical fix: Replace the spark plug. It is recommended to replace all 8 spark plugs at the same time for even performance using a quality part like ACDelco 41-162 or equivalent. 🎬 Watch: Step-by-step guide to replacing your Silverado spark plugs.
   Est. part cost: $8-$25 per plug
2. Failed Ignition Coil 🔴 High Probability
   How to confirm: Swap the ignition coil from cylinder 2 with another cylinder (e.g., cylinder 4 on the same bank). Clear the codes and drive the vehicle. If the code changes to P0304, the ignition coil is faulty.
   Typical fix: Replace the faulty ignition coil. The OEM part is often GM/ACDelco 12699383. 🎬 See how to quickly replace a failed ignition coil.
   Est. part cost: $40-$100
3. Bad Spark Plug Wire 🟡 Medium Probability A manufacturer TSB (PIP4819A) specifically calls out inspecting for loose or poorly seated spark plug wires as a cause for misfires on these vehicles. Wires can also degrade over time from extreme engine heat.
   How to confirm: Visually inspect the wire for damage, corrosion, or a loose connection at the coil and spark plug. Ensure the boot is 'clicked' on securely. Test the wire's resistance with a multimeter if a visual fault isn't obvious.
   Typical fix: Replace the spark plug wire. It's often best to replace the full set.
   Est. part cost: $50-$100 for a set
4. Clogged or Failed Fuel Injector 🟡 Medium Probability
   How to confirm: A professional can perform a fuel injector balance test. A DIY method is to swap the fuel injector from cylinder 2 with another cylinder, similar to the coil swap test. If the misfire code moves, the injector is the cause. Sometimes, using a quality fuel system cleaner can resolve minor clogs as a first step.
   Typical fix: Replace the faulty fuel injector. On 2014+ direct injection models, this is a more involved job. Sometimes, a professional fuel system cleaning can resolve a clog.
   Est. part cost: $50-$150
5. Collapsed or Stuck AFM Lifter 🟡 Medium Probability The Active Fuel Management (AFM) system used on the 5.3L and 6.2L V8s has a well-documented history of lifter failure. The lifters can become stuck or collapse, preventing the valve from opening, which causes a persistent misfire on that cylinder. This is often preceded by a distinct ticking sound.
   How to confirm: This is an advanced diagnosis. It often starts with a ticking noise from the engine. A mechanic may remove the valve cover to observe if the rocker arms for cylinder 2 are moving correctly. A compression test on cylinder 2 may show low or no compression. In a repair story, a technician found a collapsed lifter on cylinder 1 had come apart in pieces.
   Typical fix: This is a major repair that involves removing the cylinder head to replace all AFM lifters on the affected bank. The camshaft is often inspected for damage and replaced if necessary. Many owners opt to install an AFM-delete kit at this time to prevent future failures. 🎬 Watch this full repair guide for fixing a collapsed AFM lifter.
   Est. part cost: $400-$1500+ for parts alone (lifters, gaskets, possibly camshaft, fluids)

Rare But Worth Checking

• Intake Manifold Gasket Leak: A vacuum leak near the cylinder 2 intake runner can lean out the air/fuel mixture and cause a misfire. This can be diagnosed with a smoke test.
• Low Engine Compression: Beyond a failed lifter, issues like a bent pushrod, broken valve spring, or worn piston rings can cause a loss of compression and a misfire. A compression test is required to diagnose this.
• Failed Valve Lifter Oil Manifold (VLOM): The VLOM directs oil to the AFM lifters. If it malfunctions, it can cause lifters to fail to activate or deactivate properly, leading to misfires. TSB 15-06-01-002H includes replacing the VLOM as part of the lifter repair procedure.

Diagnosis Steps

1. Read the code with an OBD-II scanner and confirm P0302 is present. Note if the check engine light is steady or flashing. Use a scanner with live data to check the misfire counters for each cylinder (Mode 6 data can show historical misfires even without a current code).
2. Check for any other stored codes, especially P0300.
3. Locate cylinder 2 (front-most cylinder on the passenger side).
4. Inspect the spark plug wire for cylinder 2. Per TSB PIP4819A, ensure it is securely connected at both the ignition coil and the spark plug. Listen for a 'click'. Look for any signs of damage or arcing.
5. Swap the ignition coil from cylinder 2 with an adjacent, easily accessible cylinder (like cylinder 4 on the same bank). Clear the codes and run the engine to see if the misfire code moves to the other cylinder (e.g., P0304). If it does, the coil is bad.
6. If the code does not move, remove and inspect the spark plug from cylinder 2. If it's fouled, worn, or damaged, replace it. It's best to replace all 8.
7. If the misfire remains on cylinder 2, listen carefully for a distinct ticking sound from the passenger side valve cover area, which strongly suggests a lifter issue.
8. Perform a compression test on cylinder 2 and compare the reading to other cylinders. A significant loss of pressure points to a mechanical problem like a bad lifter, valve spring, or piston rings.
9. If compression is good, the problem may be a clogged fuel injector. Consider using a high-quality fuel injector cleaner first. If that fails, consider swapping the injector with another cylinder to confirm (this is more difficult, especially on DI engines).
10. If a mechanical issue like a lifter is suspected, the next step is typically removing the valve cover to visually inspect the valvetrain movement as the engine is cranked.

Parts You'll Likely Need

• Spark Plug (OEM #ACDelco 41-162 (replaces 41-110 for many 5.3L applications, verify by VIN)) — Spark plugs are a common wear item and the most frequent cause of a single-cylinder misfire.
  Trusted brands: ACDelco, NGK
  OEM price range: $12-$20
  Aftermarket price range: $8-$15
• Ignition Coil (OEM #12699383 (verify by VIN)) — Ignition coils are another common failure point that directly causes misfires. Swapping them is a key diagnostic step.
  Trusted brands: ACDelco, Delphi
  OEM price range: $50-$95
  Aftermarket price range: $30-$60
• AFM Lifters & Gasket Kit (OEM #12660737 (VLOM Service Kit, per TSB 15-06-01-002H, verify by VIN)) — A collapsed AFM lifter is a common major mechanical failure on these engines that causes a persistent misfire. Repair requires replacing the lifters and all associated gaskets.
  Trusted brands: ACDelco, Melling
  OEM price range: $400-$800
  Aftermarket price range: $250-$500

Related Codes That Often Appear With This One

• P0300 — If the misfire is severe or intermittent, the ECM may also log a P0300 code for 'Random/Multiple Cylinder Misfire Detected' in addition to the specific cylinder code. TSBs for lifter failure often reference P0300 as the primary code.

Technical Service Bulletins (TSBs) & Recalls

• PIP4819A: Addresses misfire codes (P0300-P0308) and instructs technicians to inspect for loose spark plug wires.
• 15-06-01-002H: A critical TSB covering engine misfire/tick noise (P0300) caused by AFM lifter failure. It details the diagnostic process, including inspecting the camshaft and replacing lifters and the Valve Lifter Oil Manifold (VLOM). It applies to 2014+ models with 5.3L and 6.2L engines.

Platform-Specific Known Issues

• Active Fuel Management (AFM) Lifter Failure: The most significant issue for the 2010-2017 V8 Silverados. The specialized lifters used to deactivate cylinders can collapse or get stuck, leading to a misfire and engine ticking. This is a well-documented problem that can require extensive engine work to repair, often including camshaft replacement if the failure is severe. A class-action lawsuit was filed against GM regarding these failures.
• Loose Spark Plug Wires: TSB PIP4819A specifically highlights that misfire codes can be triggered simply by a spark plug wire that is not fully seated on the spark plug or coil pack. It's a simple check that can save a lot of diagnostic time.
• Carbon Buildup (2014+ EcoTec3): The 3rd generation trucks with direct injection (DI) are more prone to carbon buildup on the back of the intake valves. Over time, this can restrict airflow into the cylinder, causing a lean condition and contributing to misfires. This is less common than ignition or lifter issues but is a known characteristic of DI engines.

Mechanic-Grade Diagnostic Values

• Fuel Injector Resistance (Port Injection, 2010-2013) — expected: 10-15 Ohms. Consistency is key; all injectors should be within 0.5 Ohms of each other.. Failure: A reading of 0 Ohms (shorted) or infinite/OL (open). A reading that deviates more than 20% from the others indicates a failing injector.
• Low-Pressure Fuel System (2010-2013 GMT900) — expected: 55-62 PSI.. Failure: Pressure significantly below this range indicates a weak in-tank fuel pump or clogged filter.
• Low-Pressure Fuel System (2014+ K2XX GDI) — expected: 50-75 PSI (345-517 kPa). GM Recall 13370A specifies a minimum of 73 PSI (500 kPa).. Failure: Pressure below 50 PSI points to a weak in-tank pump, clogged filter, or faulty Fuel Pump Driver Module (FPDM).
• High-Pressure Fuel System at Idle (2014+ K2XX GDI) — expected: 500-900 PSI.. Failure: Pressure significantly below 500 PSI or erratic readings can indicate a failing High-Pressure Fuel Pump (HPFP) or fuel rail pressure sensor.
• Ignition Coil Primary Resistance — expected: Typically 0.4 to 2.0 Ohms.. Failure: A reading outside the specification, though resistance tests on modern coils can be inconclusive.

Hidden / Shadow Codes Worth Checking

• Mode $06, TID $0C, CID $A3: Provides misfire counts for cylinder 2 for the last and current driving cycles. This data can reveal misfires that are not yet severe enough to set a P0302 trouble code or illuminate the check engine light. (see via A professional scan tool or an OBD-II app with Mode $06 capabilities. The Component ID (CID) $A2 through $A9 typically corresponds to cylinders 1-8.)

Scan Tool Commands That Help

• GDS2 / Professional Scan Tool: Cylinder Power Balance Test — Use this test when a P0302 is present but swapping the coil and plug does not resolve the issue. The test deactivates each cylinder one by one and measures the drop in engine RPM. If deactivating cylinder 2 causes little or no RPM drop compared to other cylinders, it confirms cylinder 2 is not contributing power, pointing towards a fuel, compression, or mechanical issue rather than spark.

Wiring & Ground Locations

• G103 — On the front of the passenger side cylinder head, just below the valve cover (for 2014+ K2XX models).. This is a primary engine control ground. Corrosion or a loose connection here can cause erratic sensor readings and misfires. Since cylinder 2 is on the passenger side, this ground is particularly relevant.
• Engine Harness Chafe Point — On 2014+ models, inspect the engine wiring harness where it can rub against the corner of the cylinder heads, the ECM/TCM bracket, the driver's side upper control arm, and the shock tower.. Multiple GM TSBs identify harness chafing as a cause for various electrical issues, including shorting out injector or ignition coil control wires. A short on the cylinder 2 circuit would directly cause a P0302.
• Braided Ground Strap — A braided ground strap connects the back of the engine/cylinder head to the frame, often located underneath the truck below the passenger side door area.. This is a critical engine-to-chassis ground. If it corrodes and breaks, it can cause a host of hard-to-diagnose electrical problems, including misfires, as various components seek a path to ground.

Real Owner Repair Stories

• YouTube channel "Ford Boss Me" (2015 Silverado 5.3L) — Persistent misfire on one cylinder (P0301 in the video, but same cause applies to P0302), flashing check engine light.
  ❌ Tried (didn't work) The video series starts after the owner had already attempted some fixes. The mechanic's diagnosis quickly moved past spark and fuel delivery.
  ✅ What actually fixed it A collapsed AFM lifter on the intake valve for the misfiring cylinder. The lifter had physically come apart into pieces inside the engine. The camshaft was inspected and found to be undamaged. Replacing the set of AFM lifters on that bank resolved the misfire.
• Reddit user in r/MechanicAdvice (2011 Silverado 1500 5.3L with 112k miles) — Intermittent P0302 misfire. Sometimes would appear immediately, other times not for a whole day.
  ❌ Tried (didn't work) Replaced spark plug on cylinder 2., Replaced spark plug wire on cylinder 2., Swapped coil packs between cylinders (misfire did not move)., Replaced the fuel injector on cylinder 2.
  ✅ What actually fixed it The user did not post the final resolution, but the story is valuable because it shows a case where all common ignition and fuel-related fixes failed to solve the P0302, strongly pointing the diagnosis toward a deeper mechanical issue like a failing AFM lifter.

"I Checked Everything" — The Actual Cause

• While no specific stories matching this pattern were found, the common AFM lifter failure acts in a similar way. A technician can confirm there is good spark, proper fuel injector function, and no vacuum leaks (a 'clean' smoke test), yet the P0302 code persists. The root cause is not external to the engine but an internal mechanical failure (the collapsed lifter) that a smoke test cannot detect.

OEM Part Supersession History

• ACDelco 41-110 (and 41-985 before it) → ACDelco 41-162 — Vendor change and/or design update for Gen IV V8 engines (pre-2014).
  Heads up: Some owners of pre-2014 vehicles report that the newer 41-162 plug is physically shorter and resulted in a rougher idle compared to the original 41-110. One Corvette owner with an LS3 engine reported a misfire at idle with the new plugs that was resolved by reinstalling the old-spec 41-110 plugs.
• GM 12660737 → GM 19433052 — Part update for the Valve Lifter Oil Manifold (VLOM) service kit, which is often replaced during an AFM lifter job.

Model Year Variations Within This Range

• 2014-2017: These models use the Gen V EcoTec3 engine with direct injection (GDI). This introduces a high-pressure fuel system (HPFP and high-pressure injectors) which is a potential failure point not present on 2010-2013 models. These engines are also known for carbon buildup on intake valves, which can cause misfires.
• 2014-2017: The K2XX platform trucks are subject to several Technical Service Bulletins (TSBs) regarding engine wiring harness chafing at specific points (ECM bracket, upper control arm), which can lead to shorts and misfires.