Safety 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.
Fuel Injectors
The solenoid operated port fuel injector is controlled by the ECM. The injector consists of a valve body with a specially ground nozzle valve. The moveable armature is attached to the nozzle valve. Nozzle valve is held against nozzle body sealing seat by spring pressure.
Electric pulses generate a magnetic field in injector solenoid wiring. This draws the armature backward against spring pressure and lifts nozzle from the seat. Spring pressure forces the nozzle valve closed. See Fig 1.
The ECM energizes the solenoid, opening the valve, allowing pressurized fuel to be injected. ECM obtains predetermined air/fuel ratio by controlling the injector energized time.
Fuel injector is installed in intake manifold at each cylinder. Injector sealing is provided with "O" ring seals. Lower "O" ring seals between injector and intake manifold. Upper "O" ring seals between injector and fuel rail. Replace "O" rings when injector is removed.
Each injector contains a wire connector. One wire supplies voltage from fuse panel. Second wire connects to ECM ground and controls injector pulse width.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.