3.2. Malfunctions of system of injection of fuel

On cars the system of the distributed fuel injection is applied. Is called distributed injection 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 and fuel profitability of the car.
In system of injection of fuel of the VAZ-21126 engine with feedback in system of release catalytic converter of the fulfilled gases and two sensors of concentration of oxygen which provide feedback are established. Sensors trace the content of oxygen in the fulfilled gases, and the electronic control unit on their signals supports such ratio of air and fuel at which converter works most effectively.

Before removing any knots of a control system of injection, disconnect a wire from the minus plug of the rechargeable battery.
Disconnect the rechargeable battery only at the switched-off ignition.
Do not launch the engine if tips of wires on the rechargeable battery are badly tightened.
Never disconnect the rechargeable battery from onboard network of the car at the working engine.
At charging disconnect the rechargeable battery from onboard network of the car.
Do not allow heating of the electronic control unit (ECU) above 65 °C in working order and above 80 °C in non-working (for example, in the drying camera after painting). If this temperature is exceeded, it is necessary to remove EBU from the car.
Do not disconnect from EBU and do not attach to it sockets of a plait of wires at the included ignition.
Before performance of arc welding on the car disconnect wires from the rechargeable battery and sockets of wires from EBU.
Carry out all voltage measurements the digital voltmeter which 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 damages of EBU by the electrostatic category:
– do not touch with hands plugs EBU or electronic components on its payments;
– during the work with the programmable read-only memory (PROM) of the control unit do not touch chip conclusions.
During the work in rainy weather do not allow hit of water on electronic components of system of injection of fuel.

Carry out an inspection of system of injection in the following order.
1. Check connection with "mass" of the engine and the rechargeable battery.
2. Check pressure regulator, the fuel filter and the fuel pump.
3. Check safety locks and the relay of inclusion of elements of system of injection.
4. Check reliability of contacts of blocks with wires of elements of system of injection.
5. Check sensors of system of injection.
The vast majority of malfunctions of system of injection of fuel is called by failure of its following sensors:
– provisions of a bent shaft — injection system crash, the engine is not started up;
– provisions of the camshaft (the sensor of phases) – transition to synchronous work of nozzles, deterioration in operational qualities (dynamics, fuel consumption);
– a mass consumption of air — increase in fuel consumption, considerable deterioration in dynamics, breakthroughs and failures, problems with launch of the engine;
– provisions of a butterfly valve — loss of power, breakthroughs and failures at dispersal, unstable work in the idling mode;
– temperatures of cooling liquid — difficulty with start-up in a frost. It is necessary to warm up the engine, supporting turns by an accelerator pedal. At an overheat power significantly decreases, the detonation appears;
– concentration of oxygen (lambda probe) – increase in fuel consumption, deceleration of power of the engine, unstable work idling (only on the cars equipped with catalytic converter). Damage of catalytic converter of the fulfilled gases is possible;
– detonations — the engine is very sensitive to quality of gasoline, the increased tendency to a detonation;
– car speeds — deterioration in dynamic qualities of the car in the modes with use of the maximum power (intensive dispersal) is possible;
– the uneven road — deterioration in operational indicators of the engine on the uneven road.