Technical characteristics of the fuel injection system (Opel Kadett E)

Operating principle

The electric fuel pump takes fuel from the tank, delivers it under pressure of 2.5 kg/cm² through the filter to the fuel line and then to the injectors (each cylinder has one injector). The fuel pressure regulator installed at the end of the fuel line maintains a constant injection pressure and drains excess fuel into the tank, i.e. ensures fuel circulation in the system and prevents the formation of fuel vapors in it.

The amount of fuel injected is determined by the controller depending on the information provided by the sensors measuring the following parameters: volume and temperature of the intake air, crankshaft speed, engine load and coolant temperature. The main parameter determining the fuel dosage is the volume of intake air measured by the air flow meter. The incoming air flow deflects the pressure flap by a certain angle, which is converted by the potentiometer into an electrical signal sent to the controller. The latter determines the amount of fuel required at the given moment for the engine to operate and sends pulses of fuel supply time to the electromagnetic valves of the injectors.



At forced idle speed, as well as when the specified crankshaft rotation speed is exceeded, the fuel supply to the injectors is stopped by the controller commands.

The air supply to the intake manifold during starting, warming up and adjusting the engine idle speed is controlled by the idle speed regulator.

Data for verification and adjustment

Engine crankshaft speed at idle, rpm: 720-780.

Carbon monoxide (CO) content in exhaust gases, no more than, %: 1.

Air filter

Air filter with replaceable dry filter element.

Fuel pump

The fuel pump is electric, rotary. The supply voltage is supplied to the pump through a relay controlled by the controller.

Brand and catalog number: Bosch 0 580 464 008.

Operating voltage, V: 7-15.

Pump performance at terminal voltage of 12 V, l/h: 60.

Fuel pressure in the system, kg/cm²:

• working: 2.0-2.2;
• unregulated (with the vacuum hose disconnected from the pressure regulator): 2,3-2,7.

Controller

The controller is installed in a sealed box behind the trim under the instrument panel on the right and is designed to determine the moment and duration of injection depending on the information received from the sensors. The controller also ensures the start and warming up of a cold engine, its operation at forced idle speed and the execution of a self-diagnostic program.

Opel catalogue number:

• cars with engine "20NE": 90 280 357;
• cars with engine "20SEH": 90 284 137.

Voltage, V:

• working: 10-15;
• when the starter is turned on - 6-15;
• with ignition off: 10-15.

Air flow meter

The air flow meter measures the amount of air entering the engine. A potentiometer mounted on the axis of the pressure flap of the meter sends a signal about the air flow to the controller. An air temperature sensor is built into the meter body.



Brand and catalog number: Bosch 0 280 202 202.

Resistance between potentiometer terminals at 20°C. Ohm:

• "2" and "4": 8-2500 (depending on the position of the pressure valve);
• "3" and "4": 300-550;
• "1" and "4": 270-520;
• "2" and "4": 10-200 (with the pressure valve in its initial position).

Air temperature sensor

Resistance between terminals "4" and "5" depending on air temperature, kOhm:

• at -10°C: 8.26-10.56;
• at + 15°C: 1.45;
• at +20°C: 2.28-2.72;
• at +30°C 3.30;
• at +50°C: 0.76-0.91.

Throttle body

The throttle body is electrically heated and is installed after the air flow meter. The position sensor of the throttle valve built into the throttle body sends signals about the engine load to the controller (idle or full throttle).

Throttle position sensor

Brand and catalog number: Bosch 0 280 120 316.

Resistance, Ohm:

• between terminal "2" (idle position) and "ground": 0;
• between terminal "3" (position "full load") and "ground": 0.

Resistance between terminals with closed throttle valve, Ohm:

• "2" and "18": 0;
• "3" and "18": infinity.

Coolant temperature sensor

The coolant temperature sensor has a negative temperature coefficient (i.e. its resistance decreases with increasing temperature) and is installed in the thermostat housing.

Brand and catalog number: Bosch 0 280 130 026.

Resistance between terminals "13" and "16". kOhm:

• at 0°C: 4.8-6.6;
• at +20°C: 2.2-2.8.
• at +40°C: 1.0-1.4;
• at +80°C: 0.27-0.38.

Fuel pressure regulator

The diaphragm type pressure regulator is installed on the fuel line and is designed to maintain constant pressure in the system.



Brand and catalog number: Bosch 0 280 160 221.

Nominal regulation pressure at atmospheric pressure in the vacuum intake nipple, kg/cm²: 2.5±0.2.

Idle speed control valve

The idle speed controller is a stepper motor that drives a rotary valve. It is installed in the air channel, which is made parallel to the throttle body, and ensures the constancy of the engine crankshaft speed at idle speed, changing the amount of incoming air using a rotary valve.

Brand and catalog number: Bosch 0 280 140 516.

Winding resistance at temperature 15-30°C, Ohm: ~8.

Engine speed and crankshaft position sensor

The engine speed and crankshaft position sensor is mounted on the cylinder block opposite a special toothed rim made on the first counterweight of the crankshaft, and generates a voltage pulse when it passes through the magnetic field of the rim.

Brand and catalog N: Bosch 0 261 210 030.

Winding resistance, Ohm: 0.5-1.6.

Sensor installation gap, mm: 1.0±0.2.

Injection nozzles with needle valve

Electromagnetic injectors are controlled by a controller that determines the moment and duration of injection.

Brand and catalog number: Bosch 0 280 150 725.

Winding resistance at +20°C, Ohm: 15-17 (4 Ohm when measured with parallel connected injectors).

One drop of fuel per minute is allowed to leak through the injector.

Damper

Brand and catalog number: Bosch 0 280 161 006.

Power relay

The injection system power supply relay is installed in the engine compartment on the left, behind the damper. The relay supplies power to the actuators and, through a 20 A fuse, to the fuel pump.

Diagnostic connector

The diagnostic connector is located on the left side of the engine compartment and serves to query the main memory of the controller about injection system faults.