1989 Pontiac Firebird Engine Management Wiring Diagram
The 1989 Firebird 2.8L V6 manual has a three-part ECM circuit. Choose the engine that matches your car, then open the source manual to read the diagrams and connector labels.
Confirm the engine first
The linked circuit is from the Firebird V6-173 2.8L manual. Separate 3.8L V6, 5.0L V8 and 5.7L V8 manual entries are listed in the archive. The 2.8L ECM pinout is not established for those engines.
The 2.8L drawings mark automatic and manual transmission branches. Follow the branch and equipment that match your vehicle.
Select your exact Firebird engineSafety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Open the three-part 2.8L ECM circuit
The source entry contains all three parts of the circuit, including sensor signals, injector and ignition control, fuel-pump control, warning-lamp and emissions connections. Read wire colors and terminal numbers in the full manual drawing before testing.
Open the 2.8L ECM diagrams in the manualSource: 1989 Pontiac Firebird V6-173 2.8L / Powertrain Management / Electrical Diagrams / Electronic/Powertrain Control Module (ECM/PCM).
Use the diagram with a test procedure
A circuit diagram shows connections; it does not diagnose a failed ECM, sensor or relay. Use the applicable diagnostic procedure and measured results before replacing a part.