Fuel Injection Timing
WARNING: This page is about a different car, the 2007 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.
The period of time the fuel injectors are energized is controlled by the PCM.
The pulse width is determined by inputs from the:
- heated oxygen sensor (HO2S).
- MAF sensor.
- engine coolant temperature (ECT) sensor.
- camshaft synchronizer.
- intake air temperature (IAT) sensor.
- Between idle and 5,800 RPM, the fuel is injected to each cylinder independently by giving 1 injection per 2 crankshaft rotations (1 injection per cycle) to all cylinders.
- Fuel injection for each cylinder takes place during its exhaust stroke.
- Above 5,800 RPM, fuel is cut to prevent engine over speeding and possible engine damage.
| Engine Speed (RPM) | Fuel Injection |
|---|---|
| Cranking | Two injections/1 crankshaft rotation (simultaneous injection to all cylinders) |
| Idle to 5,800 | One injection/2 crankshaft rotations (sequential injection to each cylinder) |
| Above 5,800 | Fuel cut |
| Fail-safe | One injection/2 crankshaft rotations (simultaneous injection to all cylinders) |