P2146 on 2010-2014 Chevrolet Equinox: Injector Circuit Fault Causes & Fixes

What's Unique About the 2010-2014 Chevrolet EQUINOX

The 2010-2014 Equinox, along with its platform mate the GMC Terrain, is specifically known for issues with its fuel injector wiring harness, particularly on the V6 models. A widely-referenced GM Technical Service Bulletin (PIP4924D) confirms the harness is prone to chafing against engine components like the intake plenum, valve cover bolts, or the side of the cylinder head, leading to shorts or open circuits. This makes a wiring inspection the number one diagnostic step, ahead of assuming the injectors or computer have failed.

Diagnostic Flowchart

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

Symptoms You May Notice

• Engine runs very rough or has a severe misfire.
• Hard starting or no-start condition.
• Significant loss of engine power and may enter 'limp mode'.
• Check Engine Light is on.
🎬 Watch: A quick overview of fixing the P2146 error code.
• Engine may stall unexpectedly.
• Poor fuel economy.

Most Likely Causes

1. Damaged Fuel Injector Wiring Harness 🔴 High Probability → Shop Engine Wiring Harness A GM Technical Service Bulletin (PIP4924D) was issued specifically for this problem, noting the harness can rub against the intake plenum, valve cover bolts, or fuel lines, causing wires to break or short out. This is a well-documented failure point on this platform.
   How to confirm: Visually inspect the entire fuel injector harness, especially where it is routed under the intake manifold and around the valve covers. Look for shiny, worn-through spots on the plastic conduit. Wiggle the harness with the engine running (if possible) to see if the misfire changes. Perform a continuity test on the wires for the Group 'A' injectors from the ECM connector to each injector connector to find the break.
   Typical fix: Repair the damaged section of the wire by soldering in a new piece and using heat-shrink tubing, or replace the entire fuel injector harness if damage is extensive or in a difficult-to-reach spot under the intake.
   Est. part cost: $10-$250
2. Failed Fuel Injector 🟡 Medium Probability → Shop Fuel Injector
   How to confirm: After accessing the injectors, measure the resistance of each injector in Group 'A' with a multimeter. Compare the readings to the manufacturer's specifications (typically 11-14 ohms). A reading that is significantly different (often infinite resistance for an open circuit) indicates a bad injector.
   Typical fix: Replace the faulty fuel injector. It is often recommended to replace them as a set if they are original and high-mileage, especially on GDI engines.
   Est. part cost: $50-$150 per injector
3. Loose or Corroded Connectors ⚪ Low Probability
   How to confirm: Inspect the electrical connectors at the fuel injectors and the main harness connectors, as well as the ECM connectors. Look for bent pins, corrosion, or signs of water/oil intrusion.
   Typical fix: Clean the connectors with electrical contact cleaner. If a connector is damaged, a pigtail replacement is often available.
   Est. part cost: $10-$50
4. Faulty Engine Control Module (ECM) ⚪ Low Probability → Shop Engine Control Module (ECM)
   How to confirm: This should be the last step after confirming all wiring and injectors are good. An ECM failure is confirmed by substitution or specialized testing of the injector driver circuit. A professional diagnosis is recommended before replacing the ECM.
   Typical fix: Replace and reprogram the Engine Control Module.
   Est. part cost: $300-$800

Diagnosis Steps

1. Scan the ECM for all stored trouble codes. Note if P2146 is accompanied by specific injector codes (P0201-P0206) or the Group 'B' code (P2149).
2. Perform a thorough visual inspection of the fuel injector wiring harness. Following the guidance of TSB PIP4924D, check for chafing against the intake plenum, valve cover bolts, fuel lines, and the side of the cylinder head. The harness is often routed tightly and can rub through its protective conduit.
3. If the engine can run, gently wiggle sections of the injector harness while listening for any change in the engine's idle. A change strongly indicates an intermittent break in the wiring.
4. Disconnect the harness from the Group 'A' injectors. This may require removing the intake manifold. Use a multimeter to check the resistance of each injector. Compare to OEM specifications (typically 11-14 ohms). An open circuit (infinite resistance) indicates a failed injector.
5. If injectors test good, perform a continuity test on the power supply and control wires from the main harness connector to each individual injector connector to find any breaks in the wiring.
6. Use a 'noid' light to test for a pulse signal at each injector connector while cranking the engine. 🎬 Watch this step-by-step guide to diagnosing injector circuit malfunctions. No flash on multiple injectors in a group points to a wiring or ECM issue.
7. If all wiring and injectors test good, the final step is to suspect a faulty injector driver circuit within the ECM. This should be confirmed by a professional before replacement.

Parts You'll Likely Need

• Fuel Injector Wiring Harness — This is the most common failure point for this code on this vehicle, as documented by a GM TSB. Damage is often found under the intake manifold.
  Trusted brands: ACDelco, Standard Motor Products
  OEM price range: $150-$300
  Aftermarket price range: $75-$200
• Fuel Injector (OEM #12633784 (For 2.4L), 12638530 (For 3.6L)) — An injector can fail internally, creating an open circuit that triggers this code. The 2.4L uses a different injector than the V6 models.
  Trusted brands: ACDelco, Bosch, Hitachi
  OEM price range: $90-$150
  Aftermarket price range: $45-$90
• Fuel Injector Connector Pigtail (OEM #ACDelco PT2160) — If only the connector at the injector is damaged or corroded, a pigtail can be spliced in, avoiding a full harness replacement.
  Trusted brands: ACDelco, Dorman, Standard Motor Products
  OEM price range: $20-$40
  Aftermarket price range: $10-$25

Related Codes That Often Appear With This One

• P0201-P0206 — These codes indicate a circuit malfunction for a specific injector (e.g., P0201 for cylinder 1). They often appear with P2146, helping to pinpoint the issue to the injector circuits.
• P2149 — This is the code for 'Fuel Injector Group 'B' Supply Voltage Circuit/Open'. Seeing both P2146 and P2149 simultaneously strongly suggests a major wiring harness problem affecting both banks or a critical ECM failure.
• P0300 — This code for 'Random/Multiple Cylinder Misfire' is a common companion, as the failure of an entire injector group will cause multiple cylinders to misfire.

Technical Service Bulletins (TSBs) & Recalls

• PIP4924D: States that for codes including P2146, technicians should inspect the fuel injector wiring harness for rubbing or internal opens at several common locations around the engine.

Platform-Specific Known Issues

• TSB PIP4924D explicitly calls out the fuel injector wiring harness for potential rub-through or internal wire opens on 2010-2014 Equinox models with V6 engines (3.0L LF1/LFW, 3.6L LLT/LFX). Common chafe points are against the intake plenum and valve cover bolts.
• On the 2.4L Ecotec engine, the harness can also chafe, but issues with the high-pressure fuel pump and timing chain are also common, though not directly related to P2146.
• Owner forums frequently discuss repairing the harness themselves. A common repair story involves removing the intake manifold to access the harness, finding a wire rubbed through to the copper, and repairing that single wire to solve the problem.
🎬 See how to repair a mangled fuel injection wiring harness.

Mechanic-Grade Diagnostic Values

• Fuel Injector Coil Resistance (GDI Engines: 2.4L, 3.0L, 3.6L) — expected: 1.8 to 2.3 Ohms at 68°F (20°C). Failure: A reading of infinite resistance (OL) indicates an open coil. A reading significantly outside the specified range indicates a faulty injector.
• Injector Connector Voltage (Key On, Engine Off) — expected: Battery Voltage (approx. 12.6V) on BOTH the power supply wire and the control wire.. Failure: 0V on the power supply wire indicates an open in the harness. 0V on the control wire (with power present on the supply wire) indicates an open injector coil.

Scan Tool Commands That Help

• GM GDS2 / Tech2: Fuel Injector Test / Balance Test — This bidirectional control allows the technician to command each injector to fire individually. If all injectors in Group 'A' (e.g., Bank 1) fail to respond during this test, it confirms the issue is with the group's circuit (harness or ECM driver). If only one injector fails to respond, it isolates the fault to that specific injector or its dedicated wiring.

Wiring & Ground Locations

• Bank 1 (Group A) Injectors — On V6 models, this is the bank of cylinders against the firewall (rear bank). Cylinders 1, 3, and 5.. P2146 specifically refers to the circuit for this group of injectors. Knowing which bank is 'A' focuses the physical inspection.
• ECM Connector X1 (V6 Engines) — On the Engine Control Module (ECM), which is typically mounted in the engine bay near the fuse block or firewall.. This connector contains the control and supply voltage pins for the injector banks. For example, on a 3.6L LFX, the Bank 1 supply voltage may be on pin 5, and injector control signals on pins like 31, 47, and 48. Testing at these pins can confirm if the ECM is sending the signal and if the harness has continuity without having to access the injectors directly.
• G103 / G104 — Main engine/transmission ground straps, typically bolted to the engine block and/or transmission case and connected to the chassis.. While less likely to cause a single-bank code, a poor engine ground can introduce electrical noise and voltage drop issues that can affect ECM operation and trigger various faults. It's a foundational check for any complex electrical issue.

Real Owner Repair Stories

• terrainforum.net user post (2011 GMC Terrain 3.0L V6 (Equinox platform twin)) — Check engine light with codes P2146, P2149, P0201, P0203, P0205. Engine running rough.
  ❌ Tried (didn't work) A repair shop replaced the Engine Control Module (ECM), which did not fix the problem.
  ✅ What actually fixed it A GM dealer technician found a chafed wire in the fuel injector harness located under the intake manifold. Repairing the single damaged wire resolved all codes.
• YouTube channel 'Schrodinger's Box' (2012 Chevrolet Equinox 3.6L V6) — Severe misfire, Check Engine Light with code P2146.
  ❌ Tried (didn't work) Initial diagnosis pointed towards injectors or ECM.
  ✅ What actually fixed it The mechanic removed the intake manifold and inspected the injector harness. He found one wire for the #3 injector had rubbed through its insulation against a sharp edge on the engine block. He repaired the wire with solder and heat shrink, which completely fixed the issue.
• chevroletforum.com user post (2011 Chevrolet Equinox 3.0L V6) — Code P2146, rough running.
  ❌ Tried (didn't work) A dealership diagnosed a bad ECM and quoted over $1000 for replacement.
  ✅ What actually fixed it The owner took the vehicle to an independent mechanic who suspected the known harness issue. He found a broken wire in the injector harness near the Bank 1 (rear) valve cover. Splicing the wire fixed the problem for a fraction of the cost of an ECM replacement.

OEM Part Supersession History

• 12638530 → 12669384 — Standard design revision or supplier change for improved performance or longevity.
  Heads up: None. The new part number is a direct, backward-compatible replacement for the original.

Model Year Variations Within This Range

• 2010-2012: The 3.0L V6 engine (LF1, LFW) was a common option. While the P2146 fault is identical, the physical shape of the intake manifold and harness routing differs slightly from the later 3.6L engine.
• 2012-2014: The 3.6L LFX V6 became the primary V6 option. It has a different intake manifold design compared to the 3.0L. The TSB (PIP4924D) regarding harness chafing applies to both engine families, but the exact point of contact may vary slightly between them.