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Computers and Control Systems: Description and Operation

The Motronic fuel injection system uses one electronic control unit (ECU) to control the fuel injection and ignition controls.

To determine the engine's ignition advance and fuel requirements, the ECU analyzes the following inputs from various sensors:
^ engine speed and position
^ intake air flow
^ intake air temperature
^ engine temperature
^ throttle valve position
^ exhaust gas composition

The ECU controls all of the injectors simultaneously and delivers its atomized fuel upstream of the intake valves. The system is also equipped with an idle regulation electrovalve, a self-diagnostic feature which alerts the operator of vehicle malfunctions through the ``Check Engine'' lamp, a canister purge electrovalve for fuel vapor recovery and a detonation sensor providing optimum engine performance.