Answer
Aug 03, 2025 - 05:29 PM
On most GMC vehicles—especially those with V6 or V8 engines—the fuel injector connectors typically have two wires per injector:
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One wire is usually pink or pink with a stripe — this is the 12V ignition power feed shared across all injectors.
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The other wire is color-coded uniquely per cylinder — this is the ground-side control wire coming from the ECM (Engine Control Module).
Common injector wire color Setup (example for V8):
| Cylinder | Wire 1 (Power) | Wire 2 (ECM Control) |
|---|---|---|
| #1 | Pink | Light Blue |
| #2 | Pink | Dark Blue |
| #3 | Pink | Light Green |
| #4 | Pink | Brown |
| #5 | Pink | White |
| #6 | Pink | Dark Green |
| #7 | Pink | Orange |
| #8 | Pink | Gray |
Note: These colors can vary slightly depending on year and engine model (e.g., 5.3L LS vs 4.3L V6 vs 6.0L Vortec).
How to connect:
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Pink wire connects to a 12V ignition-on power source (shared across all injectors).
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The second wire (varies by cylinder) connects to the corresponding ECM output pin.
If you're unsure of the engine or model year, feel free to let us know your exact GMC model and year, and we can help find the exact wiring diagram for your injector harness.
