P0267 on 2010-2015 Chevrolet Equinox: Injector Circuit Low Causes and Fixes

What's Unique About the 2010-2015 Chevrolet EQUINOX

For this generation of Chevrolet Equinox, particularly those with the 3.0L and 3.6L V6 engines, General Motors has issued multiple Technical Service Bulletins (TSBs) that directly address code P0267. These bulletins point to a known issue where the engine wiring harness is routed too closely to engine components. It can rub against the valve cover, valve cover bolts, fuel lines, or the side of the cylinder head, causing wires to short to ground. This makes a wiring fault a higher-than-usual probability compared to other vehicles where the injector itself might be the primary suspect.

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
• Rough idle or engine stumbling
• Noticeable loss of power and poor acceleration
• Engine hesitation or misfiring
• Hard starting or longer than usual engine cranking
• Reduced fuel economy
• Starter-type chatter noise during cranking (noted in TSB #PIT5424).

Most Likely Causes

1. Engine Wiring Harness Damaged or Shorted 🔴 High Probability Multiple GM Technical Service Bulletins (TSBs) for the Equinox, especially V6 models, specifically mention this. The harness can rub against the valve cover, fuel lines, or the side of the cylinder head, causing a short circuit.
   How to confirm: Visually inspect the entire engine wiring harness. TSB #PIT5424 points to the harness rubbing the rear of the bank #2 (left side) valve cover and its bolt heads. TSB #PIP4924D suggests also checking where the harness is near the intake plenum and fuel lines. Look for chafed, melted, or broken wires. The damage is often found on the back side of the engine and can be difficult to see without a mirror and flashlight.
   Typical fix: Repair the damaged section of wire using solder and heat shrink. Protect the harness from future damage by re-routing it or by adding a protective wire loom 🎬 Watch: How to fix common GM fuel injector wiring issues or high-temperature tape. Secure the harness away from sharp edges or hot surfaces.
   Est. part cost: $5-$50
2. Faulty Fuel Injector 🟡 Medium Probability
   How to confirm: Swap the cylinder 3 fuel injector with one from another cylinder (e.g., cylinder 1). Clear the codes and run the engine. If the code changes to P0261 (Cylinder 1 Injector Circuit Low), the injector is faulty. Alternatively, test the injector's internal resistance with a multimeter; it should be within manufacturer specs (typically between 11-14 ohms for the 2.4L engine, but verify for your specific part).
   Typical fix: Replace the faulty fuel injector. It is often recommended to replace all injectors as a set if they are original and have high mileage, especially on direct injection engines.
   Est. part cost: $40-$120
3. Bad Injector Connector or Pins ⚪ Low Probability
   How to confirm: Inspect the electrical connector at the fuel injector for corrosion, bent or backed-out pins, or a loose fit. Gently wiggle the connector while the engine is running to see if it affects the idle.
   Typical fix: Clean the connector with electrical contact cleaner or replace the connector pigtail if it's damaged. Dorman and ACDelco offer replacement pigtails.
   Est. part cost: $10-$30

Rare But Worth Checking

• Faulty Engine Control Module (ECM): This should be the last item to consider after thoroughly checking the wiring and the injector. The internal driver circuit in the ECM for the #3 injector can fail, but it is uncommon.
• Weak Internal Fuel Injector Spring: In some cases, the internal return spring of the injector can weaken, which may cause a decrease in the expected reference voltage, triggering a P0267 code. This would be diagnosed as a faulty injector via the swap test.

Diagnosis Steps

1. Use an OBD-II scanner to confirm P0267 and check for any other codes, such as P0303 or other injector circuit codes.
2. Perform a detailed visual inspection of the engine wiring harness. Pay close attention to the areas highlighted in GM TSBs: the routing near the ECM, the upper rear of the engine, and any points where the harness is close to valve cover bolts or fuel lines, especially on V6 models.
3. Inspect the electrical connector on the cylinder 3 fuel injector for damage, corrosion, or loose pins.
4. If no wiring damage is found, swap the cylinder 3 fuel injector with an injector from a different cylinder (e.g., cylinder 1).
5. Clear the codes, start the vehicle, and see if the fault code returns for the new cylinder (e.g., P0261). If it does, the fuel injector is the problem.
6. If the P0267 code returns after the swap, the issue is in the wiring harness or the ECM.
7. Use a multimeter or a noid light to test for voltage and a pulsing ground signal at the injector connector. A noid light is the safest way to verify the control signal. 🎬 Watch: How to diagnose a fuel injector circuit malfunction An absence of the correct signal points to a wiring or ECM issue.
8. If all tests on wiring and the injector pass, the ECM is the most likely cause and may need professional diagnosis or replacement.

Parts You'll Likely Need

• Fuel Injector (OEM #ACDelco 12634126 (for 3.0L/3.6L V6) or 12633784 / 217-3444 (for 2.4L I4)) — If the injector itself has an internal short or open, it will cause this code. This is confirmed by swapping the injector and seeing if the code follows it to a new cylinder.
  Trusted brands: ACDelco, Bosch, Hitachi
  OEM price range: $90-$150
  Aftermarket price range: $40-$90
• Wiring Repair Supplies — Per TSBs, a chafed or shorted wire in the engine harness is a highly probable cause. You may only need wire, solder, and electrical tape or heat shrink to fix it.
  OEM price range: $5-$20
  Aftermarket price range: $5-$20
• Fuel Injector Connector Pigtail (OEM #Dorman 645-215) — If the connector itself is damaged or corroded, it will need to be cut out and replaced with a new pigtail.
  Trusted brands: ACDelco, Dorman
  OEM price range: $20-$40
  Aftermarket price range: $10-$25

Related Codes That Often Appear With This One

• P0303 — P0303 means 'Cylinder 3 Misfire Detected'. Since P0267 indicates a problem with the fuel injector circuit for cylinder 3, the cylinder won't get the proper amount of fuel, directly causing a misfire.
• P0261, P0264, P0270 — These are 'Circuit Low' codes for other cylinders. If they appear with P0267, it strongly suggests a wiring harness problem affecting multiple injector circuits, as described in TSB #PIT5424.
• P0641 — This code for 'Sensor Reference Voltage 'A' Circuit/Open' can appear alongside P0267 and other injector codes, as noted in TSB #PIT5424. This points towards a more significant short in the engine harness affecting a 5-volt reference circuit.

Technical Service Bulletins (TSBs) & Recalls

• Bulletin #PIT5424: Warns of harness routing issues near the ECM and rear of the engine causing various injector circuit codes, including P0267, on 3.6L V6 engines.
• Bulletin #PIP4924D: Points to SES lights and misfires with injector codes due to the fuel injector wiring harness rubbing through against engine components on a wide range of GM vehicles with V6 engines.

Platform-Specific Known Issues

• A known issue documented in TSB #PIT5424 involves the engine harness being routed too close to the rear of the bank #2 (left side) valve cover and fastener bolt heads on the 3.6L V6 engine, leading to a short.
• TSB #PIP4924D notes that on various GM V6 engines, including those in the Equinox, the injector harness can rub against the intake plenum, valve cover bolts, or fuel lines, causing opens or shorts.

Mechanic-Grade Diagnostic Values

• Fuel Injector Internal Resistance (2.4L Engine) — expected: 11 to 14 Ohms. Failure: A reading outside this range indicates an electrically faulty injector.
• Fuel Injector Internal Resistance (General) — expected: 10 to 18 Ohms. Failure: A reading outside of the specified range for the vehicle suggests the injector's internal coil is failing.
• Injector Pulse Width During Cold Start — expected: Nearly double the normal idle pulse width for the first ~60 seconds.. Failure: This is a normal condition for emissions reduction and can cause a temporary rough idle; it should not be mistaken for a fault. The pulse width should drop by about 50% after the warm-up period.
• High Pressure Fuel Rail Pressure at Idle (Direct Injection) — expected: 1.9-5.0 MPa (276-725 PSI). Failure: Pressure outside this range could indicate a problem with the high-pressure fuel pump or sensor, not necessarily the injector circuit itself, but can affect overall fuel system diagnosis.

Scan Tool Commands That Help

• GDS2 / Tech 2 / Professional Scan Tool: Fuel Injector Balance Test — This bidirectional test commands the ECM to pulse each injector individually while monitoring fuel pressure drop. It's used to confirm if an injector is mechanically clogged or flowing differently than others, which a resistance test can't detect. The pressure drop for each injector should be within 1.5 PSI of the others.
• GDS2 / Professional Scan Tool: Cylinder Power Balance — This function allows the user to disable one cylinder at a time and observe the corresponding drop in RPM. If disabling cylinder 3 causes little or no change in RPM, it confirms that cylinder is not contributing power, reinforcing the diagnosis of a fault in that cylinder's fuel or ignition system.

Wiring & Ground Locations

• G101 — Left front of the engine compartment.. This is a primary chassis ground. A poor connection here can cause a multitude of electrical issues, including erratic sensor readings and module behavior.
• G104 — Right rear corner of the engine compartment.. Serves as a ground point for various engine components. Corrosion or looseness can create intermittent electrical faults.
• G109 — On the 2.4L, it's at the top right rear of the engine. On the 3.6L, it's at the right front of the engine.. As a direct engine ground, its integrity is critical for the proper operation of sensors and actuators mounted on the engine, including the fuel injectors.
• G112 — On the 2.4L, it's at the lower left front of the engine. On the 3.6L, it's at the left rear of the engine.. Another key engine ground point. A bad ground here was specifically cited in a forum as a potential cause for a 'No Communication with ECM' error after an engine rebuild, which could present as various circuit codes.
• Injector #3 ECM Pin — At the Engine Control Module (ECM) connector. A specific wiring diagram is needed for the exact pin number.. This is the terminus of the injector control circuit. Testing for a pulsing ground signal at this pin can definitively isolate the fault to either the ECM (if no signal is present) or the wiring/injector (if a signal is present but the fault persists).

Real Owner Repair Stories

• Chevy Equinox Forum (2011 Equinox) — No crank, 'No communication with ECM' code after engine rebuild.
  ❌ Tried (didn't work) Checking all fuses multiple times., Swapping with a known-good spare ECM.
  ✅ What actually fixed it The user did not post the final fix, but another member strongly advised re-checking all engine and body grounds, specifically naming one near the alternator, one on the back of the cylinder head, and the main block ground under the lower radiator hose, implying a bad ground was the highly likely cause.

OEM Part Supersession History

• Not specified → 12633784 (also listed as 217-3427) — Standard part evolution and replacement.
  Heads up: Part 12633784 is specified for the 2.4L engine in the Equinox and Terrain.
• Not specified → 12634126 — Standard part evolution and replacement.
  Heads up: Part 12634126 is specified for the 3.0L and 3.6L V6 engines.

Model Year Variations Within This Range

• 2010-2012 vs 2013-2015 (V6 models): The V6 engine option changed in 2013. The 2010-2012 models used a 3.0L LF1 V6, while 2013-2015 models used a more powerful 3.6L LFX V6. While both are susceptible to the TSB-documented wiring harness issues, the physical routing and specific chafe points may differ slightly due to engine geometry. The fuel injector part number (12634126) appears to be consistent across both V6 engines in this generation.