3.2. Malfunctions of system of injection of fuel

On the car the system of the distributed injection of fuel with feedback 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 of the car.
In this section the malfunctions of system of injection caused by failure of these or those sensors are only briefly described. The order of removal and installation of knots of feed and control systems is given by the engine in the subsections "Power Supply System" and "Control System of the Engine".
In system of injection with feedback catalytic converter of the fulfilled gases and the sensor of concentration of oxygen in the fulfilled gases (on the Ford Fusion car two converters and four sensors of concentration of oxygen in parallel are each other established), which provides feedback is established. Sensors trace concentration of oxygen in the fulfilled gases, and the electronic control unit on their signals supports such ratio of air and fuel at which converters work most effectively. And as the main operating sensors serve the sensors installed on a katkollektor, and the sensors installed at the exit of converters, – diagnostic, they define quality of work of all control system of the engine in general. If the control unit of the engine according to diagnostic sensors finds excess of concentration of oxygen in the fulfilled gases, not removable calibrating of system on signals of the operating sensors and meaning what - or malfunction of system, it will include an alarm lamp of malfunction of a control system of the engine in combinations of devices and will enter into memory an error code for the subsequent diagnostics.

Preventions
Before removing any knots of system of injection of fuel, disconnect a wire from the minus plug of the rechargeable battery.
Switch-off 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 as the raised current at charging can put electronic components out of action.
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). 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 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 with an 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 damage 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.
Work on ethylated gasoline of the engine with converter is not allowed — it will lead to bystry failure of converter and the sensor of concentration of oxygen.
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 the fuel pump and its fuel filter.
3. Check safety locks and the relay of inclusion of elements of system of injection.
4. Check reliability of contacts in 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:
– the sensor of provision of a bent shaft — injection system crash, the engine is not launched;
– the sensor of provision of a butterfly valve (it is established in a cover of throttle knot) – loss of power, breakthroughs and failures at dispersal, unstable work in the idling mode;
– the sensor of temperature of cooling liquid — difficulty with start-up in a frost as it is necessary to warm up the engine, supporting turns by an accelerator pedal, at an overheat power significantly decreases, the detonation appears;
– the sensor of temperature of the arriving air and absolute pressure (depression) in an inlet pipe — at refusal of function of measurement of temperature increase in fuel consumption, increase in level of toxicity of the fulfilled gases, and at refusal of function of measurement of an expense increase in fuel consumption, considerable deterioration in dynamics, a problem with launch of the engine;

Note
On the shown engine two electromagnetic valves are installed: on one for inlet and final camshafts.

– the detonation sensor — the engine is very sensitive to quality of gasoline, the increased tendency to a detonation;
– the sensor of concentration of oxygen in the fulfilled gases (lambda probe) – increase in fuel consumption, deceleration of power of the engine, unstable work idling. Damage of catalytic converter of the fulfilled gases is possible;
– the phase sensor — power deceleration, increase in fuel consumption.