Page 242 - 05. Subyek Teknik Mesin - Automobile Mechanical and Electrical Systems Automotive Technology Vehicle Maintenance and Repair (Vehicle Maintenance Repr Nv2) by Tom Denton

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226 Automobile mechanical and electrical systems

Figure 2.296 Electronic control units

Figure 2.297 Injector. (Source: Bosch Media)

The electronic diesel control units are provided with data signals from sensors and
switches attached to the engine, the pump and other vehicle systems. The sensors
are used for comparisons to programmed operating parameters and for calculations
for metering the amount of fuel delivered and for controlling the injection advance.
Injection advance is obtained by rotation of the cam ring by pump body pressure
in the injection advance mechanism. The injection advance mechanism consists
of a transverse timing device piston and control components and an electrical
solenoid valve. Maximum advance is 40° of crankshaft rotation.

A needle motion sensor in the injector sends a signal to the engine ECU at the
instant of opening of the injector ( Fig. 2.297 ). This point, relative to the crankshaft
rotational angle before TDC, is used for load and speed injection timing
calculations and for control of the EGR valve.