Fig. 2-214. Placement of the KSUD elements "Digifant 3.0/3.2" by car:
1 — adsorber;
2 — electromagnetic valve for purging the adsorber;
3 — connector of the oxygen content sensor in the exhaust gases;
4 - potentiometric throttle position sensor;
5 - idle switch;
6 — controller;
7 — fuel pressure regulator;
8 — pipe for measuring carbon monoxide (CO) content in exhaust gases;
9 — pipe for measuring fuel pressure in the system;
10 — ignition unit;
11 - spark plugs;
12 — ignition distributor;
13 - coolant temperature sensor;
14 - connector with central pin;
15, 16 — knock sensor connectors;
17 — crankshaft speed sensor connector;
18 — connecting block of injection system injectors;
19 — idle speed stabilization valve;
20 — crankshaft speed sensor;
21, 23 - knock sensors;
22 — crankcase ventilation system control valve;
24 - distribution line with injectors;
25 — intake air temperature sensor;
26 — adsorber.
Details of the KSUD "Digifant 3.0/3.2" are shown in Fig. 2-215.
Fig. 2-215. Fuel injection control subsystem KICS parts "Dlgifant 3.0/3.2":
1 - air filter;
2 — heated air intake pipe;
3 - air duct;
4 — throttle body;
5 — controller;
6 - upper part of the intake manifold;
7 - gasket;
8 - coolant temperature sensor;
9 - lower part of the intake manifold;
10 — crankshaft speed sensor;
11 — idle speed stabilization valve;
12 — crankcase ventilation system control valve;
13 — exhaust gas oxygen content sensor.
The fuel injection control subsystem consists of the following main elements.
[The original can be viewed on the portal vwmanual.ru]
The system controller, installed in the engine compartment behind the front shield, determines the optimal moment of fuel injection depending on the information provided by the system sensors.
The submersible fuel electric pump is installed in the fuel tank. Fuel supply pressure is 3 kgf/cm². Pump performance at terminal voltage of 12 V is 675 cm³/30 s.
The fuel pressure regulator is installed at the bottom of the fuel distribution line. The regulation pressure at idle with the vacuum hose connected is 2.5 kgf/cm²; with the vacuum hose disconnected about 3 kgf/cm². The residual fuel pressure in the system 10 minutes after the fuel pump stops is not less than 2 kgf/cm². The coolant temperature sensor is installed in the coolant supply housing to the cylinder head, and the intake air temperature sensor is on the air filter housing. Resistance of the sensors at air or coolant temperature:
- at 0°C: 5.0-6.2 kOhm;
- 10°C: 3.5-4.5 kOhm;
- 20°C: 2.0-3.0 kOhm;
- 30°C: 1.5-2.0 kOhm;
- 40°C: 1.0-1.5 kOhm;
- 50°C: 0.70-0.95 kOhm;
- 60°C: 0.50-0.75 kOhm;
- 70°C: 0.4-0.5 kOhm;
- 80°C: 0.225-0.375 kOhm;
- 90°C: 0.20-0.27 kOhm;
- 100°C: 0.175-0.225 kOhm.
The throttle body, mounted at the top of the intake manifold, has an idle switch and a potentiometric throttle position sensor. The idle switch is located on the throttle body. The position of the sensor is adjustable. The potentiometric throttle position sensor is also mounted on the throttle body.
Part of the fuel injection control subsystem CSM "Digifant 3.2" includes an electromagnetic idle speed stabilization valve installed in the air duct, which is made parallel to the throttle body.
The injection nozzles are installed in the lower part of the intake manifold. The resistance of the injector winding is 15-20 Ohm. The resistance of the injector winding of the 1st cylinder is measured between terminals "1" and "5" (injector connector block), injectors of the 2nd cylinder - between terminals "2" and "5", injectors of the 3rd cylinder - between terminals "3" and "5" and injectors of the 4th cylinder - between terminals "4" and "5".
The adsorber is installed on the right front wheel housing. The electromagnetic valve for purging the adsorber, installed on the right front wheel housing, is controlled by the commands of the system controller.
The exhaust gas oxygen sensor with a built-in electric heating element is installed in the exhaust pipe before the catalytic converter. The sensor sends a voltage signal to the controller proportional to the oxygen content in the exhaust gases when the sensor temperature reaches 300°C. The output voltage when starting the engine is 11 V.
Data for verification
Crankshaft speed at idle 725-875 rpm. Carbon monoxide (CO) content in exhaust gases no more than 0.5%.
Visitor comments