Table of contents: FENIX 1B System 🠇 BOSCH MONOPOINT MA 3.0 system 🠇 MAGNETI MARELLI G5 AND G6 SYSTEMS 🠇
The fuel system consists of a fuel tank, which is installed under the bottom of the car (with electric fuel pump), immersed in the tank, a fuel filter, feed and return hoses, a single-nozzle fuel injector, and a fuel pressure regulator. In addition, there is an electronic control unit (ECU), various sensors, and electrical components. The air cleaner contains a disposable paper filter element and includes an intake air temperature control system.
Caution! The fuel system is constantly under pressure, even when the engine is off.
The ECU fuel injection system is a self-tuning system that monitors and stores data to ensure optimum engine operating conditions under various loads. When the battery is disconnected, the data is erased and to restore it, you must start the engine and keep it idling until the system is adjusted. This process is best accomplished by conducting a road test for 15 minutes at 2500-3500 rpm.
FENIX 1B System
The Fenix IB system is a combined ignition and fuel injection system. Using inputs from various sensors, the electronic control unit calculates the optimum fuel injector pulse duration and ignition timing to ensure the engine operating conditions.
The electronic control device receives signals from the following sensors:
- engine speed sensor;
- manifold Absolute Pressure Sensor;
- intake air temperature sensor;
- throttle position sensor;
- coolant temperature sensor;
- oxygen sensor.
The idle speed is controlled by the electronic control unit via the idle speed control valve.
The oxygen sensor allows the electronic control unit to control the fuel mixture within limits that allow the use of a catalytic converter.
The electronic control unit continuously varies the fuel mixture, idle speed and ignition timing to ensure efficiency at all operating conditions and reduce exhaust emissions.
BOSCH MONOPOINT MA 3.0 system
Engine Management System Bosch MA3.0 (ignition/fuel injection system) includes a catalytic converter and a fuel vapor management system, and meets the latest emission control standards. The system works as follows. A fuel pump, immersed in the fuel tank, delivers fuel from the fuel tank to the fuel injector through a filter. The fuel pressure in the system is controlled by a pressure regulator. The regulator allows excess fuel to return to the fuel tank.
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;
- micro switch - tells the ECU when the throttle is closed (that is, when the fuel pedal is not pressed);
- crankshaft position sensor - informs the ECU of the engine speed and crankshaft position;
- vehicle speed sensor (on the gearbox).
MAGNETI MARELLI G5 AND G6 SYSTEMS
The Magneti Marelli engine management system is installed on XU5 engines. The system operates in a similar way to the Bosch Monopoint MA 3.0. The electrical control system consists of an ECU along with the following sensors:
- manifold Absolute Pressure Sensor - tells the ECU the vacuum in the intake manifold;
- crankshaft position sensor - informs the ECU of the engine speed and crankshaft position;
- throttle potentiometer - tells the ECU the position of the throttle valve open or closed;
- coolant temperature sensor - tells the ECU the engine temperature;
- fuel mixture temperature sensor - informs the ECU of the temperature of the fuel mixture entering the engine;
- lambda sensor (oxygen) - informs the ECU of the oxygen content in the exhaust gases.
In addition, the ECU adapts to the reduced battery voltage by changing the injector pulse width and changing the initial throttle position (additional engine) to increase idle speed.
To process signals from sensors, a digital method is used using data previously entered into the system memory.
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 enters the backup mode, the warning lamp 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.
Attention! When working on the fuel system, it is necessary to first relieve the pressure in the system.