10.8.4. Sensors of a control system of the engine

The sensor of temperature of cooling liquid represents a termistor (the resistor which resistance changes depending on temperature). The sensor will screw in taking-away union of the thermostat and it is connected to a controler entrance. At low temperature resistance of the sensor high, and at high temperature – low (tab. 10.8).

EBU counts temperature of cooling liquid on power failure on the sensor. On the cold engine power failure high, and on heated-up – low. The temperature of cooling liquid influences the majority of characteristics which EBU operates.

For sensor replacement you will need a key «on 19».

1. Disconnect a wire from the minus plug of the storage battery.

2. Partially merge cooling liquid from a radiator.

3. Compress a clamp of a block of a plait of wires...	4.... also disconnect a block from the sensor of temperature of cooling liquid.

5. Weaken a key a sensor inhaling...	6.... also turn out it from the thermostat union.

7. Cool the sensor to air temperature. Connect a tester in an ohmmeter mode to conclusions of the sensor and measure its resistance. Measure by the thermometer the current air temperature and compare the received values to tab. 10.8. At a resistance deviation from norm replace the sensor.	8. For resistance measurement on sensor conclusions at various temperature modes lower the sensor in hot water and check change of its resistance in process of water cooling, supervising water temperature the thermometer. Nominal rates of resistance at various temperature are specified in tab. 10.8.

9. Establish the sensor as it should be, the return to removal.

10. Fill in cooling liquid.

The sensor of a detonation attached to the top part of the block of cylinders, catches abnormal vibrations (detonation blows) in the engine.

Sensitive element of the sensor is the pyezokristallichesky plate. At detonation emergence on an exit of the sensor impulses of tension which increase with increase of intensity of detonation blows are generated. EBU on a signal of the sensor regulates an ignition advancing for elimination of detonation flashes of fuel.

For sensor replacement you will need a key «on 10».

1. Disconnect a wire from the minus plug of the storage battery.

2. Press a spring clamp and disconnect a block of a plait of wires from a block of a plait of the sensor of a detonation.	3. Turn out a bolt of fastening of the sensor of a detonation to the block of cylinders of the engine...

4.... also remove the sensor (the inlet pipeline is for descriptive reasons removed).

Note Pay attention to sensor marking that at replacement on new to get the similar sensor of a detonation.

5. Establish the sensor upside-down, having screwed a bolt of its fastening the moment of 19,5-20,5 N · m.

The combined sensor of temperature and absolute pressure of air in the inlet pipeline. The sensor of absolute pressure is executed in the form of four resistors of variable resistance connected by the bridge and pasted on a diaphragm which is compressed or stretched depending on absolute pressure of inlet air in the inlet pipeline. It fixes change of pressure in the inlet pipeline depending on change of loading and frequency of rotation of a cranked shaft of the engine and will transform it to tension of a target signal. EBU submits on the sensor supply voltage 5 In and processes its signals transferred on a chains of a signal transmission. Depending on a signal of the EBU sensor changes duration of supply of fuel and a corner of an advancing of ignition.

The sensor of temperature of inlet air represents a termistor with negative temperature factor: electric resistance of the sensor decreases with temperature increase. According to information on air temperature from the sensor the controler regulates amount of injected fuel.

For sensor replacement you will need a screw-driver with a crosswise edge.

1. Wring out a plastic clamp of a block of a plait of wires...	2.... also disconnect a block from the sensor.

3. Turn out two screws of fastening of the sensor of temperature and absolute pressure of inlet air to the inlet pipeline...	4.... also remove the sensor.

Note Pay attention to sensor marking that at replacement of the faulty sensor to get the similar sensor of temperature and absolute pressure of inlet air.

5. Establish the sensor of temperature and absolute pressure of inlet air as it should be, the return to removal.

The sensor of speed of the car is established on a transmission. The principle of operation of the sensor is based on effect of the Hall. The sensor gives out on EBU rectangular impulses of tension with the frequency, proportional speed of rotation of driving wheels.

For sensor replacement you will need a key «on 10».

1. Disconnect a wire from the minus plug of the storage battery.

2. Compress a spring clamp of a block of a plait of wires and disconnect a block from the sensor of speed.	3. Turn out a bolt of fastening and remove the sensor of speed.

4. Establish the sensor of speed as it should be, the return to removal.

The sensor of provision of a butterfly valve (DPDZ) is established sideways on throttle knot and connected with a butterfly valve axis.

It represents a potentiometer on which one end supply voltage "plus" (5 moves In), and other its end is connected to "weight". From the third conclusion of a potentiometer (from the toddler) there is a target signal to EBU. When the butterfly valve turns (from impact on a management pedal), tension on an exit of the sensor changes. At the closed butterfly valve it is lower than 0,95 V.Kogda a zaslonka opens, tension on an exit of the sensor grows and at completely open zaslonka there should be more than 4 V.Otslezhivaya target tension of the sensor, EBU corrects supply of fuel depending on a corner of opening of a butterfly valve (i.e. at will of the driver). DPDZ does not demand adjustment as the electronic block perceives idling (i.e. complete closing of a butterfly valve) as a zero mark.

At failure of the sensor of a butterfly valve of EBU brings in memory a code of malfunction of the sensor, includes a control lamp of a control system of the engine and counts expected value of a corner of opening of a butterfly valve on frequency of rotation of a cranked shaft and on signals of the combined sensor of temperature and absolute pressure of air in the inlet pipeline.

For DPDZ replacement you will need a screw-driver with a crosswise edge.

1. Disconnect a wire from the minus plug of the storage battery.

2. Press a clamp of a block of a plait of wires...	3.... also disconnect a block from the sensor.

4. Turn out two screws of fastening...	5.... also remove the sensor of provision of a butterfly valve from throttle knot.

6. Establish the sensor as it should be, the return to removal.

The regulator of idling (RHH) regulates frequency of rotation of a cranked shaft in an idling mode, operating amount of submitted air bypassing the closed butterfly valve. It consists of the bipolar step-by-step electric motor and the konusny valve connected to it. The valve is put forward or cleaned on EBU signals. Completely put forward needle of a regulator (that there correspond 0 steps) blocks an air stream. When the needle is moved, the consumption of air proportional to quantity of steps of a withdrawal of a needle from a saddle is provided.

Replacement of RHH is described in section 5 "Engine" (see. «Check and replacement of a regulator of idling»).

The sensor of provision of a cranked shaft of inductive type is intended for synchronization of operation of the electronic control unit with VMT of pistons of the 1st and 4th cylinders and the angular provision of a cranked shaft.

The sensor is established on a coupling case opposite to a setting gear wreath of a flywheel. On a flywheel teeths with ravnoudalenny hollows are cut out. Two teeth is cut off for creation of an impulse of synchronization (a "basic" impulse) which is necessary for coordination of operation of the control unit with VMT of pistons in the 1st and 4th cylinders.

At rotation of a cranked shaft teeths change a magnetic field of the sensor, directing impulses of tension of an alternating current. The control unit determines frequency of rotation of a cranked shaft by signals of the sensor and gives out impulses on nozzles.

At failure of the sensor start-up of the engine is impossible.

For sensor replacement you will need a key «on 10».

1. Disconnect a wire from the minus plug of the storage battery.

2. Press a spring clamp...	3.... also disconnect a block of a plait of wires of a control system of the engine from a block of a plait of wires of the sensor.

4. Turn out a bolt of fastening of the sensor...	5.... take out a block of a plait of wires of the sensor from an arm...

6.... also take the sensor of provision of a cranked shaft from an opening in a coupling case.

7. Establish the sensor as it should be, the return to removal.

The sensor of concentration of oxygen is established in a reception pipe of system of production of the fulfilled gases. Oxygen containing in fulfilled gases reacts with the sensor of concentration of oxygen, creating a potential difference on a sensor exit. It changes approximately from 0,1 In (the high content of oxygen – a poor mix) to 0,9 In (not enough oxygen – a rich mix).

For normal work the temperature of the sensor should make not below 300 °C. Therefore for fast warming up after engine start-up the heating element is built in the sensor.

Tracing target tension of the sensor of concentration of oxygen, the controler defines, what team on correction of structure of a working mix to submit on nozzles. If the mix poor (a low potential difference on a sensor exit), the controler gives command for mix enrichment; if a mix rich (a high potential difference) – on mix pauperization.

For replacement of the operating sensor of concentration of oxygen it be required to you: a key «on 22», a screw-driver with a flat edge.

1. Disconnect a wire from the minus plug of the storage battery.

2. Put forward a red clamp...	3.... also separate blocks of plaits of wires of a control system of the engine and the sensor of concentration of oxygen.

4. Turn out the sensor from a reception pipe and remove it from the car.

Note Pay attention to sensor marking that at replacement on new to get the similar sensor of concentration of oxygen.

5. Establish the sensor as it should be, the return to removal, having greased previously a carving part of the sensor with graphitic greasing.

The sensor of phases is established in a back part of a head of the block of cylinders. The principle of its action is based on effect of the Hall. The sensor defines VMT of a step of compression of the piston of the 1st cylinder. The signal of the sensor is used by the controler for the organization of the phased injection of fuel according to an operating procedure of cylinders. At emergence of malfunction of a chain the controler brings its code in the memory and includes a control lamp.

For replacement of the sensor of phases you will need a key «on 8».

1. Disconnect a wire from the minus plug of the storage battery.

2. Press a spring clamp of a block of a plait of wires...	3.... also disconnect a block from the sensor socket.

4. Turn out two bolts of fastening of a cover of the sensor to its case...	5.... also uncover with established in it a sensitive element and the socket.

Note Sensitive element of the sensor of a phase приклепан to a cover rivets therefore we recommend to replace it assembled with a cover.

6. Establish the sensor of phases as it should be, the return to removal.