Electronic Control Unit

The Electronic Control Unit (ECU) continually corrects air/fuel mixture, based on signals from oxygen sensor. The ECU sends signals to differential pressure regulator, located on the fuel distributor. See Figure . See ENGINE CONTROL/FUEL SYSTEM APPLICATION and ECU LOCATION tables.

CIS-E and CIS-Motronic fuel injection systems perform basic air-measuring and fuel-metering in the mixture control unit. The mixture-control unit is actually a combination of two separate components. The airflow sensor and fuel distributor, deliver proportional amounts of pressurized fuel to the injectors. The fuel distributor has electronic input and output control devices to help accurately control the volume of fuel delivered under various operating conditions. The system consists of mixture control unit (airflow sensor and fuel distributor), control pressure (warm-up) regulator, auxiliary air regulator, cold start valve, thermo time switch, fuel injectors, fuel pump, filter, oxygen sensor, ECU, differential pressure regulator and catalytic converter.

The CIS-Motronic engine management system uses a single control unit for fuel injection, idle speed control, ignition, and emission controls. Basic fuel injection and idle control are similar in CIS-E and CIS-Motronic. The oxygen sensor in the CIS-Motronic system can adjust its range in response to changes in operating conditions.