P0202 on 2005-2013 Chevrolet Corvette: Injector Circuit Malfunction Fixes

What's Unique About the 2005-2013 Chevrolet Corvette

On the C6 Corvette's LS series V8s, the fuel rail and injectors are very accessible, making diagnosis and repair more straightforward than on many other vehicles. While the code itself is a standard SAE definition, the most common failure point is simply the injector itself, rather than complex wiring issues. Owners on forums frequently resolve this code by replacing the single faulty injector after confirming with a swap test. Checking the connector is always a critical first step, as engine heat and vibration can degrade the connection over time.

Symptoms You May Notice

• Check Engine Light is on
• Rough or uneven engine idle
• Engine misfire, which may feel like a stumble or shake
• Hesitation or loss of power during acceleration
• Reduced fuel economy
• A smell of gasoline from the exhaust
• Service Traction Control or Service ESC messages (in some GM platforms, as noted in NHTSA ODI #10705647)
• Reduced Engine Power mode (as reported in NHTSA ODI #10809597)

Most Likely Causes

1. Faulty Cylinder 2 Fuel Injector 🔴 High Probability → Shop Fuel Injector Injectors are electro-mechanical parts with a finite lifespan and can fail internally from heat cycles and mileage. The internal coil winding can break, creating an open circuit.
   How to confirm: Swap the cylinder 2 injector with another injector (e.g., cylinder 4, the next one back on the same side). Clear the codes. If the code changes to P0204, the injector is confirmed bad. You can also test the injector's resistance with a multimeter; it should be around 12 ohms for a stock LS3/LS7 injector. An open circuit will show infinite resistance. 🎬 Watch: How to diagnose a fuel injector circuit malfunction
   Typical fix: Replace the faulty fuel injector. It is recommended to replace the O-rings on adjacent injectors that are removed for access and apply a small amount of clean motor oil or silicone grease to the new O-rings for installation.
   Est. part cost: $80-$120
2. Poor Electrical Connection at Injector 🟡 Medium Probability Engine vibration and heat can cause the injector connector to become loose or the contacts within it to become corroded or spread, leading to an intermittent open circuit.
   How to confirm: Visually inspect the connector for damage, corrosion, or pushed-out pins. Disconnect and reconnect it firmly, ensuring it 'clicks' into place. Wiggle the connector with the engine running to see if the misfire changes. A 'noid light' can be used to confirm if an electrical pulse is reaching the connector.
   Typical fix: Clean the connector terminals with electrical contact cleaner. Apply a small amount of dielectric grease to the seal to keep out moisture. If the connector is damaged or terminals are loose, replace it with a new pigtail connector (e.g., GM Part #88988963 or aftermarket equivalents like ICT Billet WPINJ40X8).
   Est. part cost: $10-$25
3. Damaged Wiring Harness ⚪ Low Probability While less common, the wiring harness can chafe against engine components, brackets, or become brittle from heat, leading to an open or short in the circuit. Manufacturer service bulletins for other GM V8 platforms, such as TSB Bulletin #PIE0802A, have noted instances where technicians needed to replace both the wire harness and the affected fuel injector to resolve P0202.
   How to confirm: Perform a continuity test on the two wires for the cylinder 2 injector from the injector connector back to the PCM connector. Check for any shorts to ground or to power. A visual inspection tracing the wire from the injector back into the main loom may reveal rub marks or heat damage.
   Typical fix: Repair the broken or shorted section of wire. Solder the connection and protect the repaired area with heat-shrink tubing and high-quality tape or loom.
   Est. part cost: $1-$10

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is very rare. The internal driver circuit for the injector can fail. This should only be considered after all other possibilities (injector, wiring, connectors) have been exhaustively ruled out. In some GM vehicles, as described in NHTSA ODI #10705647, an ECM replacement was recommended after the engine experienced spitting, sputtering, and multiple injector codes including P0202.

Diagnosis Steps

1. Verify the code with an OBD-II scanner. Note any other codes present, especially P0302.
2. Locate cylinder #2. On the Corvette V8, this is the front-most cylinder on the passenger side of the engine.
3. Inspect the wiring and electrical connector at the #2 fuel injector. Look for any obvious signs of damage, corrosion, or looseness. Ensure the connector is fully seated.
4. Perform a 'noid light' test. Disconnect the injector harness and plug in the appropriate noid light. Start the engine. The light should flash rapidly, indicating the PCM and wiring are sending a pulse. 🎬 Watch: How to test injector circuits with a noid light If it flashes, the wiring is likely good and the injector is the primary suspect. If it does not flash (or stays on solid), the problem is in the wiring or the PCM driver.
5. If a noid light is not available, perform an injector swap. First, relieve fuel system pressure at the Schrader valve on the driver's side fuel rail (use a rag to catch fuel). Disconnect the battery. Unbolt the four 10mm bolts holding the fuel rail to the intake manifold. 🎬 Watch: How to remove LS fuel rails and injectors Gently pry the rail up, the injectors may stay in the rail or the intake.
6. Reassemble, clear the codes, and run the engine. If the code returns as P0204 ('Injector Circuit / Open - Cylinder 4'), the injector is faulty and needs to be replaced. If P0202 returns, the problem is in the wiring or PCM.
7. If the wiring is suspected, use a multimeter to check for continuity on both wires between the injector connector and the PCM connector. Also check for a short to ground or power on the control wire.

Parts You'll Likely Need

• Fuel Injector (OEM #12576341 (ACDelco #217-1621)) — This is the most common cause of a P0202 code. The internal coil of the injector fails, creating an open circuit.
  Trusted brands: ACDelco, Bosch
  OEM price range: $80-$120
  Aftermarket price range: $50-$90
• Fuel Injector Connector Pigtail (OEM #88988963 (ACDelco #PT2183)) — If the connector housing is cracked or the terminals are corroded or spread, replacing the pigtail is the correct repair.
  Trusted brands: ACDelco, ICT Billet
  OEM price range: $20-$30
  Aftermarket price range: $10-$20

Related Codes That Often Appear With This One

• P0302 — P0302 means 'Cylinder 2 Misfire Detected.' Since P0202 indicates a fueling problem for cylinder 2, a misfire is the direct result. A P0202 code will almost always be accompanied by a P0302.
• P0200 — P0200 is a general code for 'Injector Circuit Malfunction.' It may appear alongside a more specific code like P0202 if the PCM detects a broader issue affecting the injector control system, though it's less common to see both.

Technical Service Bulletins (TSBs) & Recalls

• TSB Bulletin #PIE0802: This manufacturer bulletin notes that the Check Engine Lamp may illuminate with DTC P0202 set. It provides a checklist for technicians to follow when investigating this specific circuit fault.
• TSB Bulletin #PIE0791B: This record indicates that manufacturer information gathering has concluded regarding the Check Engine Lamp illuminating with DTCs P0202 and P0203 set.

Platform-Specific Known Issues

• Real Repair Story: Intermittent P0202: A 2006 Z06 owner on CorvetteForum reported an intermittent P0202 code that would appear on startup, sometimes after hard driving. The owner first tried cleaning the connector and applying dielectric grease, but the code returned. They then proceeded to swap the injector from cylinder #2 to another cylinder. During the swap, an O-ring was torn, but after replacing the O-ring and completing the swap, the code did not return, suggesting the issue was resolved by simply re-seating the injector and its electrical connector securely.

Mechanic-Grade Diagnostic Values

• Fuel Injector Coil Resistance (LS3/LS7/LS9) — expected: ~12.0 Ohms. Failure: Infinite resistance (open circuit) or a value significantly different from the other injectors.
• Fuel Injector Coil Resistance (LS2) — expected: ~12-14 Ohms (Bosch style). Failure: Infinite resistance (open circuit) or a value significantly outside the range of the other injectors.
• Injector Connector Voltage (Key On, Engine Off) — expected: 12V (Battery Voltage) on the power supply wire (typically Pink).. Failure: No voltage indicates a problem with the power supply from the fuse block.
• Tech 2 Scan Tool - Injector Balance Rate — expected: Between -6.9 mm³ and +4.0 mm³ at idle in Park/Neutral.. Failure: A high positive number on cylinder #2 suggests the PCM is adding fuel to compensate for a weak injector. A large negative number could indicate a leaking injector. This test is more for performance issues than an open circuit code.

Scan Tool Commands That Help

• GM Tech 2 / GDS2: Fuel Injector Balance Test — This function commands the PCM to turn off individual injectors one by one while monitoring the drop in engine RPM. If disabling cylinder #2 causes no change in engine speed or feel, while disabling other cylinders does, it confirms cylinder #2 is not contributing, strongly pointing to a fuel/spark issue for that cylinder. For a P0202, this confirms the circuit fault is causing a complete lack of injection.
• GM Tech 2 / GDS2: Cylinder Power Balance — Similar to the injector balance test, this allows a technician to disable injectors at various engine speeds and loads, not just at idle. This can help diagnose intermittent issues that only appear under specific driving conditions.

Wiring & Ground Locations

• Injector #2 Control Wire — From the injector #2 connector to pin 49 on the C1 (X1) 'Blue' connector at the Engine Control Module (ECM). The wire color is typically Light Blue/Black.. This is the specific wire the ECM grounds to fire the injector. A break, chafe, or short-to-ground on this wire is a direct cause of P0202. Testing continuity from pin 49 at the ECM to the injector connector is a definitive wiring test.
• Injector Power Supply Wire — A Pink wire that runs from the Underhood Fuse Block (likely the 'ODD INJ' fuse) and splices to feed all odd-numbered injectors on Bank 1 (1, 3, 5, 7). A separate circuit feeds the even-numbered injectors on Bank 2.. While a failure here would typically cause codes for all four cylinders on Bank 2 (P0202, P0204, P0206, P0208), a fault at the splice point closest to injector #2 could potentially cause an isolated issue.
• G107 (Engine Block Ground) — Located on the rear of the passenger-side cylinder head. It's a critical ground point for the ECM and sensor data.. While not directly for the injector circuit itself, a poor engine ground can cause erratic behavior in the entire engine management system, leading to phantom codes. Ensuring this ground is clean and tight is a crucial step in any electrical diagnosis.

OEM Part Supersession History

• Varies by year → 12576341 (for LS3/LS7/L99) — Part consolidation and minor updates over the production run.
  Heads up: Part number 12576341 is for the shorter LS3/LS7 style injector (40mm O-ring to O-ring) and will NOT fit the 2005-2007 LS2 engine, which requires a longer 'mid-length' injector (approx. 48-53mm). The LS2 injector is part number 0280158049 or equivalent.

Model Year Variations Within This Range

• 2005-2007 (LS2 Engine): These models use a physically longer 'mid-length' style fuel injector (Bosch 0280158049, GM 12570798). They are not interchangeable with the shorter injectors used in 2008+ models.
• 2008-2013 (LS3, LS7, LS9 Engines): These models use a shorter 'mini-delphi' or 'USCAR' style injector (GM 12576341). These are the most common type for the C6 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:

• LS7 Valve Guide Wear 🔴 High — A widely discussed issue primarily affecting 2006-2013 Z06 (LS7) models. Can occur at varying mileages. GM acknowledged the concern in TSB 13-06-01-003H. (Ref: TSB 13-06-01-003H)
• Harmonic Balancer Wobble / Failure 🔴 High — Common across all C6 models (LS2/LS3/LS7). The rubber bonding delaminates, causing a wobble that can throw the belt or damage the crankshaft if it fails completely. Often preceded by a 'chirping' sound. (Ref: TSB 05-06-01-001A (for early 2005 models with loose bolt, but delamination issue affects all years))
• Fuel Level Sending Unit Failure 🟠 Medium — A very common problem where the fuel gauge becomes erratic or reads empty after filling up, often triggering a 'Service Fuel System' message and codes like P2068. The cause is often sulfur deposits on the sender contacts.
• Fuel Pump Module Leaks (2005-2008) 🔴 High — Early C6 models can develop cracks in the fuel pump module outlet, leading to a strong fuel smell, especially after filling the tank, and potential fuel leaks.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used OEM fuel injector from a low-mileage donor vehicle is a reasonable choice for a DIY repair on a budget. Since the most common failure is a sudden open circuit rather than gradual wear, a functioning used injector often has significant life left. They are simple to swap if another one fails.

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

What to inspect on the donor part:

• Check for a clean, corrosion-free electrical connector.
• Ensure the plastic body of the injector has no cracks or signs of heat damage.
• Verify the O-rings are present and not brittle or flattened, though you should always replace them anyway.
• If possible, ask the seller to test the resistance with a multimeter before purchase; it should read around 12 ohms.

Aftermarket brands forum-validated for this vehicle:

• Bosch (often the OEM supplier)
• Fuel Injector Connection (FIC)
• Injector Dynamics (for high-performance builds)

Brands owners have reported issues with on this vehicle:

• Unnamed, no-brand injectors from online marketplaces should be avoided. They often have inconsistent flow rates and poor quality control, which can cause tuning and drivability issues even if they resolve the P0202 code.

Real Owner Stories

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

Related OBD-II Codes

• P0302 — Cylinder 2 Misfire Detected — often accompanies P0202 because a circuit fault prevents the injector from fueling the cylinder properly.
• P0204 — Injector Circuit / Open - Cylinder 4 — this code will appear if a faulty cylinder 2 injector is moved to cylinder 4 during diagnostic swapping.
• P020X — Generic injector circuit codes that follow the same diagnostic flowchart provided in GM technical documentation for the C6 Corvette.

Frequently Asked Questions