Table of contents: Injection system Magneti Marelli 8P…🠇 Bosch Motronic MP5.2 injection system 🠇
The fuel injection system is an ECU self-tuning system that monitors and stores data that ensures optimal engine operating conditions under various loads. When the battery is disconnected, the data is erased and to restore it, you need to start the engine and keep it idling until the system is adjusted. This process will be best accomplished by conducting a road test for 15 minutes at 2500-3500 rpm.
Injection system Magneti Marelli 8P and Bosch Motronic MP5.1.1
The Magneti Marelli 8P fuel injection system is installed on engines with a working volume of 1.6 liters (BFZ), and Bosch Motronic MP5.1.1 is installed on 1.8 liter engines (LFY) and on 2.0 liter engines (RFV).
Both systems (ignition/fuel injection system) include a catalytic converter and evaporative emission control system, and meet the latest emissions control standards.
The fuel system in both injection systems is similar and works as follows. The fuel pump, immersed in the fuel tank, supplies fuel from the tank to the fuel injector through the filter. The fuel pressure in the system is controlled by a pressure regulator. The regulator allows excess fuel to return to the fuel tank when the pressure in the fuel system is exceeded.
The electrical control system consists of the ECU together with the following sensors:
- throttle potentiometer - tells the ECU the position of the throttle valve open or closed;
- coolant temperature sensor - tells the ECU the engine temperature;
- intake Air Temperature Sensor - Tells the ECU the temperature of the air passing through the throttle valve;
- lambda sensor - informs the ECU of the oxygen content in the exhaust gases;
- crankshaft position sensor - tells the ECU the engine speed and crankshaft position;
- manifold Absolute Pressure Sensor - tells the ECU the vacuum in the intake manifold;
- vehicle speed sensor - tells the ECU the speed of the vehicle;
- a knock sensor installed in the cylinder block is used to detect the onset of detonation or early ignition (this allows the ECU to select the optimum ignition timing for the prevailing engine operating conditions without the risk of engine damage). Installed only in the Motronic system.
Text taken from the website (PEUGEOTBOOK.ru)
All the information from the sensors is analyzed by the ECU, and based on this, the ECU determines the appropriate ignition timing and fuel mixture composition. The ECU controls the fuel injectors by changing the pulse width, i.e. the length of time the injector is open, to provide a richer or leaner mixture.
The ECU also controls the idle speed. For this purpose, there is a motor that controls the position of the throttle valve.
The ECU also controls the exhaust gas composition and the evaporative emission control system.
The electric heating element is located in the throttle body.
If there is an error in any of the data received from the sensor, the ECU enters the backup mode. In this case, the ECU ignores the incorrect sensor signal and accepts a pre-programmed value that will allow the engine to continue running (although with less efficiency). If the ECU is in the backup mode, the warning light on the instrument panel will light up and the fault will be recorded in the ECU memory. After that, it is necessary to perform a full test of the engine management system using a special electronic diagnostic test bench, which is simply plugged into the diagnostic connector of the system, located near the fuse box on the panel.
Bosch Motronic MP5.2 injection system
The Bosch Motronic MP5.2 injection system is installed on 2.0-liter engine models without a catalytic converter (r6E engine).
The MP5.2 injection system is similar to the MP5.1.1 system described above, but it does not have a lambda sensor or a fuel vapor emission system.