DME System: Description

The 944 models are equipped with the Bosch Digital Motor Electronic (DME) engine control system. The DME system uses various data sensors which monitor intake air volume, speed, crankshaft position, coolant temperature, intake air temperature, and throttle position switch. Signals from these sensors, as well as a start signal and oxygen sensor signal, are sent to the control unit.

The Control Unit (CU) is a microcomputer. It is the "brain" of the DME system. Using information obtained from data sensors, the CU determines the correct amount of fuel and optimum ignition timing.

The 944 DME control unit switches from open loop to closed loop operation when the coolant temperature is above 113°F (45°C), and when the oxygen sensor temperature is above 480°F (250°C).