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
Fuel injector nozzles are solenoid operated valves which both meter and atomize fuel delivered to engine. Injectors are mounted in lower intake manifold with their nozzles injecting fuel just upstream of engine intake valves.
Injector bodies consist of solenoid actuated pintle and needle valve assembly. Electrical control signal from ECA unit activates injector solenoid, causing pintle to move inward off seat, allowing fuel to flow.
Since injector flow orifice is fixed and fuel pressure at injector tip is constant, fuel flow to engine is regulated by how long solenoid is energized. This length of time is known as "pulse width". Atomization spray is obtained by shape of pintle.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.