Operation CHARM: Car repair manuals for everyone.
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Engine Control Module: Description and Operation

Engine Control Module

The Engine Control Module (ECM) is the heart of the vehicle's fuel delivery system. It monitors information from several inputs to determine the fuel delivery strategy required to produce efficient operation. As the sophistication of the fuel injection system increases, the amount of information processed by the ECM also increases Additional strategies to cover fueling requirements for situations such as cold starting, hot starting, and wide-open throttle acceleration may also be added to the ECM software.