Measures to improve the composition of exhaust gases (Mondeo 1)

To reduce the content of nitrogen oxides (NOx) in the exhaust gases, the diesel engine fuel system is equipped with an exhaust gas recirculation system (EGR system). The EGR valve is located on the intake manifold. The valve's task is to divert part of the exhaust gases back into the engine's combustion chambers to reduce the combustion temperature and, as a result, reduce the content of toxic substances in the exhaust gases.

To reduce other toxic substances in exhaust gases, such as particles and hydrocarbons (HC), precise electronic control and the use of an oxidation catalyst are necessary. The electronic control unit receives information from various sensors and regulates fuel injection according to specified specifications.

A measuring device is located in the suction pipe, which measures the mass of the sucked-in air according to the following principle: an electrically heated spiral is cooled by the air flow passing by. In order to maintain the temperature of the spiral constant, the heating current changes according to the density/temperature of the sucked-in air. Based on the fluctuations in the heating current, the control device determines the mass of the sucked-in air.

The sensor measures the position of the high-pressure fuel pump lever, which is activated by the gas pedal.

An inductive sensor is located on the engine flywheel. It provides information about the current engine speed.

The control unit of the injection system in a diesel engine selects the optimum moment of fuel injection under any vehicle operating conditions by adjusting the magnetic switch for cold engine operation and the magnetic valve for partial load in the high-pressure fuel pump.

The exhaust gas recirculation system is regulated by the control device through two valves, the so-called vacuum converter and the exhaust gas recirculation valve.