3.2. Malfunctions of system of injection of fuel

On the car the system of the distributed injection of fuel with feedback is applied. Distributed injection is called because fuel is injected into each cylinder by a separate nozzle. The system of injection of fuel allows to reduce toxicity of the fulfilled gases at improvement of road performance of the car.

In this section malfunctions of system of the injection, caused by failure of these or those sensors only are briefly described. The order of removal and installation of knots of power supply systems and engine management is given in the subsections "Power supply system" and «An electronic control system of the engine».

In injection system with feedback establish catalytic converter of the fulfilled gases and the sensor of concentration of oxygen in the fulfilled gases which provides feedback. The sensor traces concentration of oxygen in the fulfilled gases, and the electronic control unit on its signals supports such ratio of air and fuel at which converter works most effectively.

Preventions Before removing any knots of system of injection of fuel, disconnect a wire from the minus plug of the storage battery. The storage battery disconnect only at the switched-off ignition. Do not start up the engine if tips of wires on the storage battery are badly tightened. Never disconnect the storage battery from an onboard network of the car at the working engine. At a charging disconnect the storage battery from an onboard network of the car as the raised current at a charging can put out of action electronic components. Do not allow heating of the electronic control unit (EBU) above 65 °C in working condition and higher than 80 °C in non-working (for example, in the drying chamber). It is necessary to remove EBU from the car if this temperature is exceeded. Do not disconnect from EBU and do not attach to it sockets of a plait of wires at the included ignition. Before performance of electroarc welding on the car disconnect wires from the storage battery and sockets of wires from EBU. All measurements of tension carry out the digital voltmeter with internal resistance not less than 10 megohms. The electronic knots applied in system of injection, are calculated on very small tension therefore the electrostatic category can easily damage them. Not to allow EBU damage by the electrostatic category: – do not touch with hands EBU tips or electronic components on its payments; – at work with a programmed constant memory (PPZU) of the control unit do not touch chip conclusions. Work on etilirovanny gasoline of the engine with converter is not allowed — it will lead to fast failure of converter and the sensor of concentration of oxygen. At work in rainy weather do not allow water hit on electronic components of system of injection of fuel.

The vast majority of malfunctions of system of injection of fuel happens is caused by failure of its following sensors:

– the sensor of provision of a cranked shaft — an injection system crash, the engine is not started up;

– the sensor of absolute pressure (depression) in an inlet pipe — increase in fuel consumption, considerable deterioration of dynamics, a problem with engine start-up;

– the sensor of provision of a butterfly valve — capacity loss, breakthroughs and failures at the dispersal, unstable work in an idling mode;

– the sensor of temperature of cooling liquid (it is established under the ignition coil) – difficulties with start-up in a frost: it is necessary to warm up the engine, supporting turns an accelerator pedal, at an overheat the capacity essentially decreases, there is a detonation;

– the sensor of concentration of oxygen (lambda probe) – increase in fuel consumption, decrease in the engine capacity, unstable work idling. Damage of catalytic converter of the fulfilled gases is possible;

– the sensor of speed (it is established on a transmission case) – possibly deterioration of dynamic qualities of the car and increase in fuel consumption.