P0268 on 2009-2010 Saturn VUE: Cylinder 6 Injector Circuit High Causes and Fixes

What's Unique About the 2009-2010 Saturn VUE

For this generation of Saturn VUE and its platform mates (like the Chevrolet Equinox and GMC Terrain), the fuel injector wiring harness is a known weak point. A Technical Service Bulletin (TSB PIP4924D) was issued that specifically calls out these injector circuit codes, including P0268, as being commonly caused by the wiring harness rubbing through its insulation against engine components. Common chafe points are against the intake plenum, valve cover bolts, and the sharp edge of the ECM bracket. This makes a thorough wiring inspection the most critical first step, often revealing the problem before any parts are replaced.

Diagnostic Flowchart

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

Symptoms You May Notice

• Check Engine Light is on
• Engine misfire, which may be more noticeable under load
• Rough or unstable idle
• Reduced engine power and sluggish acceleration
• Poor fuel economy
• Hard starting
• Engine stumbling or lurching during steady driving

Most Likely Causes

1. Damaged Fuel Injector Wiring Harness 🔴 High Probability → Shop Engine Wiring Harness As documented in GM TSB PIP4924D, the harness is known to chafe against engine parts. Common rubbing points include the intake plenum, valve cover bolts, fuel lines, and the side of the cylinder head. Heat and vibration cause the wire insulation to wear through, leading to an open circuit (broken wire) or a short to voltage.
   How to confirm: Visually inspect the entire length of the wiring harness leading to the cylinder 6 fuel injector. Pay close attention to areas where the harness bends or makes contact with other engine components. Look for rubbed-through insulation, exposed copper wire, or melted plastic. Wiggling the harness near the injector connector while the engine is running may cause the misfire to change, indicating an internal wire break.
   Typical fix: If damage is found, repair the specific wire(s) using solder and heat-shrink tubing. If the damage is extensive or right at the connector, replace the connector pigtail. In severe cases, the entire injector harness may need replacement.
   Est. part cost: $10-$30 for a connector pigtail
2. Faulty Fuel Injector 🟡 Medium Probability → Shop Fuel Injector Injectors can fail electrically over time due to internal coil windings breaking or shorting out. While not as common as the wiring issue on this platform, it is a standard failure part on any aging vehicle.
   How to confirm: Swap the cylinder 6 fuel injector with an injector from another cylinder (e.g., cylinder 4). Clear the codes and run the engine. If the code changes to P0264 (Cylinder 4 Injector Circuit High), the injector is faulty. Alternatively, you can test the injector's internal resistance with a multimeter. For the 3.5L V6, it should be between 11-14 ohms. For the 3.6L V6, the spec is lower, around 1.5-2.5 ohms. An infinite reading (OL) or zero indicates a failed injector.
   Typical fix: Replace the failed fuel injector. It is often recommended to replace all injectors on that bank or all six at once if they are original 🎬 Watch: A general guide on how to replace fuel injectors. and high-mileage.
   Est. part cost: $50-$120 for a single injector
3. Poor Connection at Injector or PCM ⚪ Low Probability
   How to confirm: Disconnect the electrical connector at the fuel injector and the corresponding connector at the PCM. The PCM on V6 models is located at the left (driver's side) front of the engine compartment. Inspect the pins and terminals for corrosion, moisture, or being bent or backed out. Ensure the connectors click securely into place.
   Typical fix: Clean the connector terminals with a specialized electronic cleaner. If pins are bent, carefully straighten them or replace the connector if necessary. Apply a small amount of dielectric grease to the connector seal before reconnecting.
   Est. part cost: $5-$20 for contact cleaner

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is the least likely cause. The PCM's internal injector driver for cylinder 6 can fail, but all other possibilities, especially wiring and the injector itself, must be exhaustively ruled out before condemning the PCM. Replacing a PCM is expensive and requires programming to the vehicle's VIN.

Diagnosis Steps

1. Verify the Check Engine Light is on and scan for codes. Confirm P0268 is present, and note any other codes like P0306.
2. Identify Cylinder 6. On the transversely mounted V6 engines in the Vue, the cylinders against the firewall are Bank 1 (odd numbers: 1, 3, 5) and the cylinders near the radiator are Bank 2 (even numbers: 2, 4, 6). Cylinder 6 is on the radiator side, closest to the driver's side/transmission.
3. Perform a detailed visual inspection of the fuel injector wiring harness for cylinder 6, as recommended by TSB PIP4924D. Check for chafing against the intake manifold, valve covers, fuel lines, and ECM bracket.
4. If no visible damage is found, disconnect the connector at the cylinder 6 injector. Check for 12V power on one of the pins with the key on, engine off.
5. Use a noid light to test for a pulse signal from the PCM at the injector connector while cranking the engine. A flashing light indicates the PCM is trying to fire the injector and the wiring is likely intact.
6. If the noid light does not flash, check for continuity on the ground/control wire between the injector connector and the PCM connector. Also check the wire for a short to power or ground.
7. If wiring seems okay, test the fuel injector. Measure its resistance with a multimeter. Compare to spec: ~11-14 ohms for the 3.5L V6, or ~1.5-2.5 ohms for the 3.6L V6.
8. As a definitive test, swap the cylinder 6 injector with another one (e.g., cylinder 4). Clear codes. If the fault code moves to P0264, the injector is confirmed to be bad.
9. If the code remains P0268 after swapping the injector, the problem lies in the wiring or the PCM.
10. If all wiring and the injector are confirmed good, the final step is to suspect a faulty PCM, which is rare.

Parts You'll Likely Need

• Fuel Injector Wiring Connector Pigtail (OEM #ACDelco PT2712 (cross-references to 88988944)) — Often the wiring is damaged right at the connector, making a pigtail replacement the easiest and most reliable repair. This is a common failure point.
  Trusted brands: ACDelco, Dorman (e.g., 85139), Standard Motor Products
  OEM price range: $25-$45
  Aftermarket price range: $10-$30
• Fuel Injector (OEM #ACDelco 217-3158 (for 3.6L V6), Delphi FJ10631 (for 3.5L V6)) 🎬 Watch: Step-by-step fuel injector removal for the 3.5L engine. — If the injector's internal coil has failed (creating an open or short), it will need to be replaced. This is the second most likely cause after wiring issues.
  Trusted brands: ACDelco, Bosch, Delphi, GB Remanufacturing
  OEM price range: $90-$150
  Aftermarket price range: $50-$100

Related Codes That Often Appear With This One

• P0306 — P0306 means 'Cylinder 6 Misfire Detected'. Since P0268 causes the cylinder 6 injector to malfunction, the cylinder will not fire correctly, leading the PCM to also log a misfire code for that same cylinder.
• P0206 — P0206 means 'Injector Circuit/Open - Cylinder 6'. This is a related injector circuit fault. Depending on the exact nature of the electrical failure (open vs. short), either P0206 or P0268 may be stored.
• P0300 — P0300 means 'Random/Multiple Cylinder Misfire Detected'. If the wiring harness issue is causing intermittent shorts that affect the voltage supply or ground for multiple injectors, a general P0300 code may appear alongside the specific cylinder code.

Technical Service Bulletins (TSBs) & Recalls

• PIP4924D: SES Light And Misfire With Injector Codes. This TSB is the primary source indicating that wiring harness chafing is a known and common cause for a wide range of fuel injector codes, including P0268, on this and other GM vehicles. It covers codes P0201-P0206, P0261, P0262, P0264, P0265, P0267, P0268, and many others, strongly suggesting a systemic wiring issue rather than individual component failures.

Platform-Specific Known Issues

• GM Technical Service Bulletin PIP4924D explicitly covers the 2009-2010 Saturn VUE with V6 engines and lists P0268 as a potential code caused by a chafed fuel injector wiring harness. It advises technicians to carefully inspect the harness for damage against engine components before proceeding with other diagnostics.
• The transverse engine layout places the Bank 2 (even-numbered cylinders) wiring harness in a position where it is susceptible to rubbing against various brackets and the intake plenum due to engine movement.

Mechanic-Grade Diagnostic Values

• Injector Control Circuit Voltage (Key On, Engine Off) — expected: Battery Voltage (approx. 12.6V). Failure: A reading significantly lower than battery voltage or 0V indicates an open or short in the power supply wire to the injector.
• Injector Control Circuit Voltage (Engine Idling) — expected: A pulsing waveform between near 0V and a large inductive spike (60-80V) when viewed on an oscilloscope. Using a multimeter, it will show an average voltage.. Failure: A steady voltage near 0V or battery voltage indicates the PCM is not pulsing the injector, or the circuit is shorted.
• Injector Pulse Width (Engine at Idle) — expected: Approximately 2.0 - 3.5 milliseconds (ms). Failure: A value of 0 ms for cylinder 6 while others are normal confirms the PCM has disabled the injector due to the fault.

Scan Tool Commands That Help

• GM Tech 2 / GDS2: Fuel Injector Balance Test — This test is used to verify if an injector is mechanically clogged or electrically weak. The tool commands each injector to fire for a set duration while monitoring the fuel pressure drop. If the pressure drop for cylinder 6 is significantly different from the others, it points to a faulty injector. A similar 'Cylinder Power Balance' test disables one injector at a time to see the corresponding drop in engine RPM; no change for cylinder 6 confirms it's not contributing.

Wiring & Ground Locations

• G105 — At the left rear of the engine (firewall side).. This is a primary engine ground point. A loose or corroded connection here can cause erratic behavior from the ECM and its sensor inputs, potentially leading to incorrect fault codes.
• G106 — On the engine, at the left front top corner (radiator side).. This is a key ground for the engine control module (ECM). A poor connection can directly impact the injector driver circuits and cause misfires or circuit codes.
• G107 — At the rear of the engine on V6 models.. This engine-to-chassis ground is critical for the stable operation of all engine electronics. A bad connection can cause a host of unexplained electrical issues, including injector faults.
• Cylinder 6 Injector Control Wire — This wire runs from the fuel injector connector for cylinder 6 back to a specific pin on the Engine Control Module (ECM/PCM). The V6 engines in this vehicle use a GM E67 ECM.. This is the specific wire the P0268 code is monitoring. A 'Circuit High' fault means this wire is likely broken (open circuit) or shorted to a power source somewhere along its path.

Real Owner Repair Stories

• Reddit user on r/Saturn_Cars (2008 Saturn Vue 3.6L V6) — Misfires on cylinders 1, 3, and 5 (entire rear bank) with open circuit codes after replacing valve cover gaskets.
  ❌ Tried (didn't work) Testing for ground at the coil connectors, which showed a ground was present, leading to confusion.
  ✅ What actually fixed it Found a broken ground wire for the Bank 1 ignition coils. The wire had become brittle with age and broke during the previous repair. Its path was from the rear bank, looping around the front of the engine near the cam sensors, and grounding near the power steering pump reservoir. This highlights how a single broken ground can disable an entire bank of cylinders and how wiring can become fragile.

OEM Part Supersession History

• GM 12638530 (for 3.6L V6) → GM 12669384 — Standard part number update for revision or supplier change.
  Heads up: The new part number is a direct replacement. However, it is strongly recommended to replace all injectors on a bank, or all six at once, to ensure balanced fuel delivery, as mixing old and new injectors can cause performance issues.

Model Year Variations Within This Range

• 2009-2010: The VUE offered two different GM V6 engines: the 3.5L LZ4 (a pushrod design) and the 3.6L LY7 (a DOHC design). While both are port-injected, their fuel injectors have different internal resistance specifications and are not interchangeable. The 3.5L injector has a higher resistance (~11-14 ohms) while the 3.6L injector has a lower resistance (~1.5-2.5 ohms). Using the wrong diagnostic spec will lead to a misdiagnosis.