10.7.2. Work of system of injection of fuel

The controller traces data on a condition of the engine, counts the need for fuel and determines the necessary duration of supply of fuel by nozzles (impulse duration). For increase in amount of the given fuel duration of an impulse increases, for fuel supply reduction — is reduced.
The controller has ability to estimate results of the calculations and teams, to remember the modes of recent work and to work according to them. "Self-training" of the controller is the continuous process continuing during all term of operation of the car.
Fuel moves by one of two methods: synchronous, i.e. at a certain provision of a bent shaft, or asynchronous, i.e. it is independent or without synchronization with rotation of a bent shaft. The synchronous injection of fuel is applied most often. The asynchronous injection of fuel is applied generally in the mode of launch of the engine.
The controller includes nozzles consistently. Each of nozzles joins through everyone 720o turn of a bent shaft. It allows to dose more precisely fuel in cylinders and to reduce the level of toxicity of the fulfilled gases.
The amount of the given fuel is defined by a condition of the engine, i.e. the mode of its work. These modes are provided with the controller and are described below.
When the starter begins to scroll a bent shaft of the engine, the first impulse from the sensor of provision of a bent shaft causes a controller impulse on inclusion of all nozzles at once that allows to accelerate launch of the engine.
The initial injection of fuel happens every time at launch of the engine. Duration of an impulse of injection depends on temperature. On the cold engine the impulse of injection increases for giving of bigger amount of fuel, on the heated-up engine duration of an impulse decreases. After initial injection the controller is switched to the corresponding control mode by nozzles.
Start-up mode.
At inclusion of ignition the controller turns on the relay of an electrogasoline pump which creates pressure in the highway of supply of fuel to a fuel stage.
The controller checks a signal from the sensor of temperature of cooling liquid and defines amount of fuel, necessary for start-up, and air.
When the bent shaft of the engine begins to be turned, the controller forms the phased impulse of inclusion of nozzles which duration depends on signals of the sensor of temperature of cooling liquid. On the cold engine duration of an impulse is more (for increase in amount of the given fuel), on warmed up — it is less.
The enrichment mode at acceleration.
The controller monitors sharp changes of provision of a butterfly valve (on a signal of the sensor of provision of a butterfly valve), and also behind a signal of the sensor of a mass consumption of air and provides giving of additional amount of fuel due to increase in duration of an impulse of injection. The enrichment mode at acceleration is applied only to management of fuel feeding in transitional conditions (when moving a butterfly valve).
The mode of shutdown of supply of fuel when braking by the engine.
When braking by the engine with the included transfer and coupling the controller can for the short periods of time completely disconnect fuel injection impulses. Shutdown and inclusion of supply of fuel in this mode happens during creation of certain conditions on temperature of cooling liquid, frequency of rotation of a bent shaft, speed of the car and the angle of opening of a butterfly valve.
Compensation of supply voltage.
At power failure the system of ignition can give a weak spark, and mechanical motion of "opening" of a nozzle can take more time. The controller compensates it by increase in time of accumulation of energy in coils of ignition and duration of an impulse of injection.
At increase of tension of the rechargeable battery (or tension in onboard network of the car) the controller reduces time of accumulation of energy in coils of ignition and injection duration.
Fuel supply shutdown mode.
At the switched-off ignition fuel a nozzle does not move therefore spontaneous ignition of mix in the superheated engine is excluded. Besides, impulses of injection of fuel do not move if the controller does not receive basic impulses from the sensor of provision of a bent shaft, i.e. it means that the engine does not work.
Shutdown of supply of fuel happens also at excess of maximum permissible frequency of rotation of a bent shaft of the engine, equal 6200 min.-1, for protection of the engine against work on unacceptably high turns.