Injector Timing and Duration

PURPOSE
The Engine Control Module (ECM) contains memories for the basic fuel injector discharge timing and duration at various engine speeds and manifold pressures.

OPERATION
The basic discharge duration, after being read from memory, is further modified by signals sent from various sensors to obtain the final discharge duration. The most vital of these sensors are: Engine Coolant Temperature (ECT) sensor, Intake Air Temperature (IAT) sensor, Manifold Absolute Pressure (MAP) sensor, Heated Oxygen (HO2S) sensor, and the Barometric Pressure (BARO) sensor.