A fuel injection system VR6 engine
Management VR6 engine implements manufactured by ?«Bosch?» injection system Motronic, which has already established earlier in the other car firms ?«Volkswagen?» and ?«Audi?». This system is a complex electronic engine control, which is based on data received from various sensors, determines the amount of fuel injected and the ignition timing depending on the load and operating conditions. The amount of fuel injected into the cylinder and precise ignition timing determined by the electronic control unit (ECU). The data from the sensors in the form of electrical signals on the thermal state of the engine, engine speed, the amount supplied to the engine air, the degree of compression, an opening angle of the throttle position of the crank pins of the crankshaft and therefore the situation of the pistons are sent to the control unit, which processes them and uses information, thus ensuring the optimal composition of the fuel mixture at any given moment of the engine.
VR6 engine control unit has a built-in fault memory, which detects irregularities in the computer and the elements Motronic system and enters them into the computer storage device. When a fault coolant temperature sensor, intake air temperature, air flow meter potentiometer computer starts according to the value taken by "default". After returning to normal computer use values taken "default" stops.
To facilitate troubleshooting provided the opportunity of requesting the current settings through the computer and the actuation of a particular element of the system.
For troubleshooting, entered in the computer storage device, you must use diagnostic stands firm, which released the car. After troubleshooting in the workshop, they are erased from the fault memory, which allows the registrar to record a new fault faults when they are detected, do not confuse them with the old problem.
Turns of idling and the proportion of CO are regulated electronically and can not be checked and adjusted at the same time without fault memory. Idling can be measured using a specially designed engine tachometer and must be from 660 to 740 min-1. If they are not correct, you should contact the service station.
To properly measure the amount of idle speed, follow these recommendations:
- Warm up the engine to operating temperature. It should be at least 80 ?° C;
- Turn off all consumers of electric current;
- Turn off the air conditioner, if any;
- Exhaust system must be in good condition;
- Measure the proportion of CO with a special instrument. Location connect the instrument to measure CO is located next to the throttle body and is built into the exhaust pipe. Allowable proportion of CO is between 0.3 and 1.2%.
Fig. 198. Location of Motronic injection system in the engine compartment of the motor VR6: 1 - vessel with activated carbon; 2 - solenoid valve (N80); 3 - flow sensor (G70); 4 - the inlet hose; 5 - the throttle body; 6 - knock sensor ?„–1 (G61); 7 - connection with "weight"; 8 - an electronic control unit (ECU), fuel injection and ignition ?«Motronic?»; 9 - the ignition coil (N152); 10 - temperature switch; 11 - temperature sensor (G62); 12 - temperature switch; 13 - temperature sensor (G72); 14 - fuel pressure regulator; 15 - the gauge of frequency of rotation of the crankshaft (G28); 16 - knock sensor ?„–2 (G66); 17 - injectors (N30, N33, N83, N84); 18 - air filter. (The designations in brackets refer to the wiring diagram)
Location of engine control module (ECM) VR6 Motronic shown in (Fig. 198).
ECM consists of the following elements:
- A reservoir with activated carbon 1 (see. Fig. 198)
is placed on the right wheel housing;
- Solenoid valve 2 opens and closes the connection between the reservoir of activated carbon and the motor;
- Air flow sensor 3 is located in the flow of intake air through the air between the air filter and air intake hose;
- The inlet hose 4 has a connection for heating the crankcase ventilation;
- Preheating of the throttle control portion is carried out by means of a cooling fluid;
- Function of the knock sensors 6 and 16 are described in section 8;
ECU engine placed behind the instrument panel inside the vehicle;
- Function of the ignition coil 9 are described in Section 8);
- Temperature switches are closed or opened depending on the coolant temperature. The temperature switch 10 serves to turn off the air conditioner, as well as the third stage of the cooling fan. He has brown the plug connector and four-pin connector. Only available for vehicles with mounted air conditioning;
- The temperature sensor 11 has a blue plug connector and two-pin connector. It informs the computer about the temperature of the coolant;
- Temperature sensor informs the ECU 13 of the air temperature in the intake pipe;
- Speed sensor crankshaft of the engine ECU 15 provides information about the current speed of the engine crankshaft.