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ENGINE MANAGEMENT SYSTEM - V8 DESCRIPTION AND OPERATION 18-2-43 Operation - engine management Fuel quantity To achieve optimum fuel quantity under all driving conditions, the ECM provides an adaptive fuel strategy. Conditions l Cold starting. l Hot starting. l Wide open throttle. l Acceleration. All of the throttle positions mentioned above are deemed to be 'open loop'. Open loop fuelling does not rely on 2 sensors, but the air/ fuel ratio is set directly by the ECM. During cold start conditions the ECM uses ECT information to allow more fuel to be injected into the cylinders to facilitate cold starting. This strategy 2 sensors are at working temperature and can pass exhaust gas information to the ECM. Because of the specific nature of the other functions e.g. hot starting, idle, wide open throttle, and acceleration they EMISSION CONTROL - V8, DESCRIPTION AND OPERATION, Secondary air injection system. Adaptive fuel strategy also allows for wear in the engine and components, as well as slight differences in component Function l Mass air flow (MAF) sensor. l Crank speed and position (CKP) sensor. l Engine coolant temperature (ECT) sensor. l Throttle position (TP) sensor. During one engine revolution, 4 of the 8 cylinders draw in air. The ECM uses CKP sensor information to determine The ECM refers the measured air mass against a fuel quantity map in its memory and then supplies an earth path to During adaptive fuelling conditions, information from the heated oxygen sensors (HO 2 S) is used by the ECM to correct the fuel quantity to keep the air/ fuel ratio as close to the stoichiometric ideal as possible. |