1 Valve needle 2 Solenoid valve spring 3 Solenoid valve The fuel injectors are each fitted with one solenoid valve. Actuation for fuel metering is carried out by the IDM. Current is applied to the solenoid valves in two stages. At the beginning of an injection process, the solenoid valve is actuated with a higher… Read More »
The fuel metering valve regulates the quantity of fuel fed to the high-pressure chamber of the high-pressure pump as a function of fuel pressure in the fuel rail in accordance with the fuel requirements. As a result, the quantity of fuel that flows back to the fuel tank is kept to a minimum. 1 Transfer… Read More »
Using the CPP switch, the PCM identifies whether the clutch is engaged or disengaged. The quantity of injected fuel is briefly reduced during actuation of the clutch to avoid engine judder during gearshifts. The CPP switch is located on the pedal box assembly. On vehicles with a speed control system, the CPP switch switches off… Read More »
1 BPP switch 2 Stoplamp switch The signal from the stoplamp switch affects fuel metering when the brake is actuated and when a gear is engaged when idling. Example: During braking, the PCM receives a signal from the stoplamp switch which results in the fuel quantity for idle control being reduced. This prevents the idle… Read More »
A position sensor is integrated in the EGR valve, which records the instantaneous position of the valve and reports it back to the PCM. A position sensor is usually provided as follows. • Emission standard III: Only in conjunction with a fixed turbocharger (no guide vane adjustment) – in this case, no MAF sensor is… Read More »
The engine management system continually compares the fuel pressure request (calculated by the system) and the actual fuel pressure in the fuel rail (measured by the fuel pressure sensor). If the system is working properly, the two parameters will be within ± 50 bar of each other. If they differ by more than -50 bar… Read More »
The fuel pressure sensor measures the current fuel pressure in the fuel rail very accurately and quickly and delivers a voltage signal to the IDM in accordance with the current pressure level. The fuel pressure sensor signal is used to: • determine the injected fuel quantity, • determine the start of injection, • drive the… Read More »
The fuel temperature sensor is located in the fuel supply system on the rear of the high-pressure pump. It measures the fuel temperature in the low-pressure system. With the aid of this signal, the fuel temperature can be continually monitored to prevent the fuel system from overheating. Effects of faults (blue fuel temperature sensor) Open… Read More »
1 Fuel injector 2 IDM or PCM 3 KS 4 Pilot injection and main injection The KS sensor registers increased vibrations arising as a result of increased combustion noise. The signal is used by the IDM as a correction factor for adapting the fuel quantity for pilot injection and for the main injection. Correcting the… Read More »
Location Integrated into the accelerator pedal Function The PCM needs the accelerator pedal position in order to control engine power according to driver input. The APP sensor houses a total of three sliding contact potentiometers. Effects of faults Failure of a potentiometer has no influence on engine operation. Only one DTC is (as a rule)… Read More »