Engine Start-Up

This is an OPEN LOOP mode. The following inputs are received by the SBEC when the starter motor is engaged:

^ Battery voltage
^ Coolant Temperature Sensor (CTS)
^ Crankshaft Position Sensor (CPS)
^ Manifold Air Temperature (MAT) sensor
^ Manifold Absolute Pressure (MAP) sensor
^ Starter motor relay
^ Sync signal
^ Throttle Position Sensor (TPS)


If the engine controller receives an engine rotation signal from the Crankshaft Position Sensor (CPS) it will ENERGIZE the Auto Shutdown (ASD) and fuel pump relays. The auto shutdown relay supplies voltage to the fuel injectors and the ignition coil, and the fuel pump relay supplies voltage to the fuel pump and the oxygen sensor heater element. If the engine controller does not receive an engine rotation signal from the Crankshaft Position Sensor (CPS), within approximately 3 seconds of ignition switch ON signal, the fuel injection system will become DE-ACTIVATED.

The fuel injector pulse width and injector firing sequence are controlled by the engine controller. The engine controller does this by switching the ground to the injectors OFF and ON.

If the engine controller receives a wide open throttle signal from the Throttle Position Sensor (TPS), it assumes that a flooding condition exists and it removes the ground from all of the injectors. Fuel injection will not occur until engine speed reaches at least 400 rpm.

The engine controller adjusts the ignition timing for different driving conditions based upon the input received from the Crankshaft Position Sensor (CPS).