Engines and Accessories

For most people reading this article, an introduction to the Electronic Control Unit (ECU) or Electronic Control Module (ECM) of an electronically fuel injected engine is not necessary. Automobiles have been equipped with these units for over twenty years now, in varying levels of sophistication.

Essentially, the ECU or ECM is an onboard computer system that receives input from various sensors and actuators on and in the engine and delivers the programmed amount of fuel based on this input. As computer technology has increased, so has the ability to more accurately monitor engine operations. The result is more performance from less fuel.
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