P0276 on 2009-2010 Saturn Outlook: Cylinder 6 Injector Circuit Low Causes & Fixes

What's Unique About the 2009-2010 Saturn OUTLOOK

The Saturn Outlook and its GM Lambda platform siblings (GMC Acadia, Chevy Traverse, Buick Enclave) are well-known for a specific issue causing this code. A GM Technical Service Bulletin (TSB) points directly to the fuel injector wiring harness rubbing against engine components and shorting out. This makes a wiring inspection the most critical first step, as it's a more common failure than the injector itself on this particular vehicle.

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 or flashing
• Engine runs rough, especially at idle
• Hesitation or stumbling during acceleration
• Reduced engine power
• Poor fuel economy

Most Likely Causes

1. Chafed or Shorted Fuel Injector Wiring Harness 🔴 High Probability → Shop Engine Wiring Harness As documented in GM TSB #PIP4924D, the engine harness is susceptible to rubbing against the intake plenum, valve cover bolts, fuel lines, and the cylinder head. Engine vibration causes the insulation to wear through over time, leading to a short circuit.
   How to confirm: Visually inspect the entire length of the fuel injector wiring harness, focusing on the known chafe points mentioned in the TSB. Look for worn insulation, exposed copper wire, or signs of melting.
   Typical fix: Repair the damaged section of wire and protect it from future rubbing using loom or by re-routing it. In severe cases, a new connector pigtail or harness section may be needed.
   Est. part cost: $15-$50
2. Failed Cylinder 6 Fuel Injector 🟡 Medium Probability → Shop Fuel Injector The fuel injector can fail internally, causing an electrical short. While less common than the wiring issue on this platform, it is still a frequent cause for this code.
   How to confirm: Swap the cylinder 6 injector with an adjacent one (e.g., cylinder 4). Clear the codes and drive the vehicle. If the code changes to P0270 (Cylinder 4 Injector Circuit Low), the injector is faulty. Alternatively, check the injector's resistance with a multimeter; it should be between 11 and 14 ohms for this engine when tested between 50-90°F (10-32°C).
   Typical fix: Replace the faulty fuel injector. Since accessing the injectors requires removing the upper intake manifold, it's wise to replace the intake gaskets at the same time.
   Est. part cost: $60-$120
3. Poor Connection at Injector or ECM ⚪ Low Probability
   How to confirm: Inspect the electrical connector at the fuel injector and the main engine harness connectors for corrosion, moisture, or bent/loose pins.
   Typical fix: Clean the connector terminals with electrical contact cleaner and apply dielectric grease to prevent future corrosion. Reseat the connector firmly.
   Est. part cost: $5-$15

Rare But Worth Checking

• Faulty Engine Control Module (ECM): → Shop Engine Control Module (ECM) This should be the last consideration after all wiring and component checks have been exhausted. The internal driver circuit for the injector can fail, but it is uncommon.

Diagnosis Steps

1. Verify the presence of code P0276 with an OBD-II scanner.
2. Perform a detailed visual inspection of the fuel injector wiring harness for any signs of chafing, melting, or damage, as detailed in TSB #PIP4924D. Pay close attention to where the harness may contact the intake plenum, valve cover bolts, and fuel lines.
3. If no wiring damage is visible, use a noid light on the cylinder 6 injector connector to see if the ECM is sending a pulse signal.
4. If a pulse is present, suspect the injector. Swap the cylinder 6 injector with cylinder 4. Clear codes and see if the fault moves to cylinder 4 (P0270). If it does, the injector is bad.
5. If the fault remains on cylinder 6 after the swap, the problem is in the wiring.
6. Check for continuity and for a short to ground on the control wire between the ECM connector and the injector connector.
7. If wiring and the injector are confirmed to be good, the ECM may be faulty, but this is rare.

Parts You'll Likely Need

• Fuel Injector (OEM #12669384) — This is the part to replace if the injector itself has failed the resistance or swap test.
  Trusted brands: ACDelco, Bosch, Standard Motor Products
  OEM price range: $90-$140
  Aftermarket price range: $60-$100
• Fuel Injector Connector Pigtail (OEM #PT2160) — If the wiring is damaged right at the connector, replacing the pigtail is the most effective repair.
  Trusted brands: ACDelco, Dorman
  OEM price range: $25-$40
  Aftermarket price range: $15-$25
• Upper and Lower Intake Manifold Gaskets — These must be replaced whenever the intake manifold is removed to access the fuel injectors to prevent vacuum leaks.
  Trusted brands: Fel-Pro, Mahle
  OEM price range: $50-$80
  Aftermarket price range: $30-$60

Related Codes That Often Appear With This One

• P0306 — This code for 'Cylinder 6 Misfire Detected' is a direct result of the injector circuit fault indicated by P0276, which prevents proper fueling for combustion in that cylinder.
• P0206 — This is a more generic code for 'Injector Circuit/Open - Cylinder 6'. It can appear alongside P0276 and points to the same electrical fault.
• P0267 — This code is for 'Cylinder 3 Injector Circuit Low'. On the 3.6L LLT engine, the ECM pairs the drivers for injectors 3 and 6. A significant short on the cylinder 6 circuit can cause the ECM to also set a fault for cylinder 3, which strongly points to a wiring issue rather than a single failed injector.

Technical Service Bulletins (TSBs) & Recalls

• PIP4924D: Advises technicians to inspect the fuel injector wiring harness for rubbing through or internal damage when various injector codes, including P0276, are present.

Platform-Specific Known Issues

• A known issue documented in TSB #PIP4924D involves the fuel injector wiring harness rubbing through its insulation against various engine components, causing a short to ground and triggering injector circuit codes like P0276.

Mechanic-Grade Diagnostic Values

• Fuel Injector Coil Resistance (3.6L LLT Engine) — expected: 11-14 Ohms when engine coolant temp is between 10-32°C (50-90°F).. Failure: A reading significantly outside this range, or where the difference between the highest and lowest reading of all injectors is more than 3 ohms.
• Fuel Pressure (Key On, Engine Off) — expected: 384-425 kPa (56-62 psi). Failure: Pressure below this range indicates a weak fuel pump or leak. Pressure should not drop more than 34 kPa (5 psi) in one minute after the pump is turned off.
• Injector Pulse Width (at idle) — expected: Approximately 2.45 milliseconds (example value). Failure: While there's no single 'good' value as it varies with conditions, comparing the pulse width of cylinder 6 to other cylinders on a scope can reveal inconsistencies. A significantly different value could indicate a problem.

Scan Tool Commands That Help

• GM Tech 2 / GDS2: Fuel Injector Balance Test — This test helps identify a mechanically faulty or clogged injector when an electrical fault isn't obvious. The tool commands each injector to fire for a precise duration and measures the corresponding drop in fuel rail pressure. If the pressure drop for cylinder 6 is significantly different (more than 20 kPa or 3 psi) from the average of the others, it indicates a flow issue with that injector.
• GM Tech 2 / GDS2: Cylinder Power Balance — This function deactivates one injector at a time to gauge the RPM drop for each cylinder. If deactivating cylinder 6 results in little or no change in engine RPM or vibration compared to other cylinders, it confirms that cylinder 6 was not contributing power, pointing to a fault in its fuel or ignition system.

Wiring & Ground Locations

• G112 — Rear of the engine, mounted to the rear of the cylinder head.. This is a primary engine ground point for the 3.6L engine. A loose or corroded connection here can cause unstable voltage and erratic signals for multiple engine components, including the fuel injection system, potentially leading to a low voltage code like P0276.
• ECM Connector X1 — The Engine Control Module (ECM) is located on the front of the engine. X1 is the 73-pin connector.. This connector contains the pins for the Bank 1 injectors (1, 3, 5). While cylinder 6 is on Bank 2, a wiring diagram is essential to find the corresponding pin for the cylinder 6 injector control wire on its respective connector to test for continuity and shorts back to the ECM.
• Harness Chafe Point — The injector wiring harness where it passes over valve cover bolts, against the intake plenum, and near fuel lines.. This is the most common failure location as documented in TSB #PIP4924D. Engine vibration causes the harness to rub through on sharp edges, shorting the injector control wire to ground and triggering P0276.

Real Owner Repair Stories

• AcadiaForum.net user (2010 GMC Acadia (Lambda Platform sibling)) — Check engine light with codes P0276, P0300, P0306.
  ❌ Tried (didn't work) Initial diagnosis suggested a bad injector.
  ✅ What actually fixed it The user found the wiring harness chafed through on the back side of the engine block, near the firewall. The wires for the cylinder 6 injector were exposed and shorting out. Repairing the damaged wires and protecting the harness resolved all codes.

OEM Part Supersession History

• 12611545, 12632255, 12638530 → 12669384 — Standard part evolution and consolidation by the manufacturer.