Starting Mode

When the ignition is first turned ON the PCM energizes the fuel pump relay for two seconds, allowing the fuel pump to build up pressure. The PCM then checks the Engine Coolant Temperature (ECT) sensor and the Throttle Position (TP) sensor. During cranking, the PCM checks the crankshaft position signal in order to determine the proper air/fuel ratio for starting. The PCM controls the amount of fuel delivered in the starting mode by changing how long the fuel injectors are energized. This is done by pulsing the fuel injectors for very short times.