Starting Mode
When the engine control module (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 manifold absolute pressure (MAP), intake air temperature (IAT), engine coolant temperature (ECT), and the throttle position (TP) sensor signals in order to determine the required injector pulse width for starting.