What is ECM? Explain how fuel injection is controlled using ECM.

1 Answer

Answer :

ECM-The ECM is Electronic control module. It evaluates the sensor inputs using data tables and calculations to determine the output of the actuating devices. The ECM processes signals from the various sensors like Temperature, intake air flow, lambda (O2) & MAP sensors.

Fuel injection control using ECMECM controls fuel injection by calculating A: F ratio needed for engine. Engine requires different air fuel ratios while cranking, warm up, idle, normal running, and sudden acceleration. As ECM receives inputs from various sensors such as like TPS, MAP, O2 & other sensors, it calculates the injector pulse width that precisely meets the engine equirment.The ECM energizes the injector once for each piston intake stroke. The amount of fuel delivered by the injector is determined by the pulse width, or “on time” of the injector. The pulse width is measured in milliseconds (MS) and the fuel flow from the injector increases in relation to the pulse width.

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