Starting Mode
WARNING: This page is about a different car, the 2003 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
When ECM detects reference pulses from the Crankshaft Position (CKP) sensor, the ECM will enable the fuel pump. The fuel pump runs and builds up pressure in the fuel system. The ECM then monitors the Mass Airflow (MAF), Intake Air Temperature (IAT), Engine Coolant Temperature (ECT), and Throttle Position (TP) sensor signals in order to determine the required injector pulse-width for starting.