AAZ and 1Y engine

The fuel system consists of the fuel tank, the fuel pump of high pressure (FPHP), the fuel filter with a separator giving and returnable fuel tubes and four fuel nozzles.

TNVD is put in action by a gear belt. The fuel pump under high pressure via pipelines gives fuel to nozzles which are established in a head of the block of cylinders about combustion chambers. Nozzles inject fuel into vortex cameras in which there is a fuel ignition.

The nozzle represents the valve which opens with strictly certain pressure of fuel. The spray which is on the lower end of a nozzle forms a torch of the sprayed fuel of the required form. The cut-off of fuel is made by a needle under the influence of a nozzle spring. The spray and a needle are knot of precision accuracy and demand the accurate address at repair. Surplus of fuel after a cut-off is pumped over along a needle, greasing it, and on the return pipeline is taken away in a tank.

Serviceability and the correct adjustment of nozzles are very important for normal operation of the engine. If the spray of a nozzle does not provide a torch of the required form, or there is a bad cut-off, the engine begins to work with vibration, there are strong mechanical knocks, smoking increases.

For a stop of the engine there is an electromagnetic valve. At start of the engine on a winding of the valve tension moves 12 V. Klapan open and passes fuel to the pump and nozzles. At switching off of the engine the turn of a key in the lock of ignition switches off the fuel valve and fuel supply is blocked.

For simplification of start of the cold engine on early models the cable of increase in turns of idling which is controlled from the dashboard is used. On later models the cable of start of the cold engine is replaced with the automatic executive mechanism of increase in turns of idling installed on the fuel pump.

Engines 1Z, AHU and AFN

The system of direct injection of fuel contains the electronic control device (ECU), sensors and executive mechanisms.

The moment of injection of fuel is defined by position of the fuel pump. The dynamic moment of injection of fuel and duration of injection of fuel is run by the ECU block and temperatures of cooling liquid, absolute atmospheric pressure (height) and depression in an inlet collector depend on turns of the engine, size of a stream and temperature of the air coming to the engine.

Besides, the ECU block operates action of system of repeated combustion of the fulfilled gases (EGR), system of decrease in toxicity of exhaust gases, a control system of pressure created by a turbocharger and a control system of glow plugs.