Cars use a multiport fuel injection system
Spread injection is called because fuel is injected into each cylinder by a separate injector.
The fuel injection system reduces the toxicity of exhaust gases while improving driving performance and fuel efficiency of the car.
Diagnosis of the injection system using diagnostic codes is described in the "Engine management system" subsection.
When working with the injection system, be sure to adhere to the following rules:
- 1. Before removing any components of the injection control system, disconnect the wire from the "-" terminal of the battery. Disconnect the battery only when the ignition is off.
- 2. Do not start the engine if the cable lugs on the battery are loose.
- 3. Never disconnect the battery from the vehicle's electrical system while the engine is running.
- 4. When charging the battery, disconnect it from the car's electrical system.
- 5. Do not allow the electronic control unit (ECU) to heat up above 65°C in working condition and above 80°C in non-working state (for example, in a drying chamber). It is necessary to remove the computer from the car if this temperature is exceeded.
- 6. Do not disconnect or connect the wiring harness connectors to the ECU while the ignition is on.
- 7. Disconnect the wires from the battery and the wire connectors from the ECU before arc welding on the vehicle.
- 8. Perform all voltage measurements with a digital voltmeter with an internal resistance of at least 10 MΩ.
- 9. The electronic components used in the injection system are designed for very low voltage, so they can easily be damaged by electrostatic discharge.
To prevent ESD damage to the ECU:
- - do not touch the computer plugs or electronic components on its boards with your hands;
- - when working with a programmable read-only memory (PROM) of the control unit, do not touch the pins of the microcircuit.
The vast majority of fuel injection system malfunctions are caused by the failure of the following sensors:
- crankshaft position sensor (synchronization) - complete failure of the injection system, the engine does not start;
- mass air flow sensor - increased fuel consumption, significant deterioration in dynamics, problems with starting the engine;
- throttle position sensor - loss of power, jerks and dips during acceleration, unstable idling;
- coolant temperature sensor - difficulties with starting in cold weather: you have to warm up the engine, maintaining the speed with the accelerator pedal, when overheating, power decreases significantly, detonation appears;
- knock sensor - the engine is very sensitive to the quality of gasoline, increased tendency to detonation; installed on the right side of the engine
- oxygen sensor ("lambda probe") - increase in fuel consumption, decrease in engine power, unstable idling.
Possible catalytic converter damage;
- speed sensor - the impossibility of self-learning of the system to adjust to the driving style of a particular driver.
Possible deterioration of the dynamic qualities of the car in modes using maximum power (intense acceleration).
Diagnosis of the injection system using diagnostic codes is described in the article - "Diagnostics and fault codes for the Chevrolet Niva ECM with the ME17.9.71 controller"
- crankshaft position sensor (synchronization) - complete failure of the injection system, the engine does not start;