Toyota Corolla

1992-1998 of release

Repair and operation of the car

Cars are equipped with system of electronic injection of fuel (EFI system) which three subsystems – fuel system, system of an intake of air and an electronic control system enter

FUEL SYSTEM

The fuel pump located in a tank provides fuel supply under constant pressure in the distributor from which fuel is evenly distributed on nozzles. From the distributor fuel moves to inlet canals of cylinders through nozzles. The amount of injectable fuel is strictly controlled by an electronic control unit (ESM-block). The regulator of pressure of fuel provides change of pressure of fuel according to depression on the soaking-up collector. The fuel filter is mounted between the fuel pump and the distributor of fuel and intended for purification of gasoline and protection of units of system of injection against failure.

SYSTEM OF THE INTAKE OF AIR

The system of an intake of air consists of the air filter, the camera of a butterfly valve and the channel connecting these two units. The sensor of the air temperature (IAT sensor) traces temperature of the taken-away air. The signal from the sensor arrives on an electronic control unit which provides a dosage of injectable fuel according to air temperature. The driver operates a butterfly valve. In process of opening of a butterfly valve the speed of the arriving air increases that leads to decrease in its temperature. The sensor registers change of air temperature and gives a signal on the ESM block which in turn gives the signal increasing a dose of injectable fuel on nozzles.

ELECTRONIC CONTROL UNIT (ECM-BLOK)

Management of electronic injection of fuel and other systems is provided with an electronic control unit which in turn is a part of the central computer control system (CCS-system). The microprocessor is a part of the ESM-block.

On the control unit signals from a number of sensors which trace such parameters as air temperature on an entrance to cylinders, an angle of rotation of a butterfly valve, temperature of cooling liquid, engine speed, speed of the movement of the car and content of oxygen in exhaust gases arrive.

On the basis of these data the control unit determines the fuel injection duration with which maintenance of an optimum ratio of gasoline and air in gas mixture is provided. Some of these sensors and the corresponding relays working from the control unit are not a part of system of electronic injection of fuel, however are mounted on all space of a motor compartment.

More detailed description of the control unit and the systems of electric equipment of the engine operated from this block is provided in subsection 6.2.

Check

PERFORMANCE ORDER

1. Check reliability of all connections with weight. Check conducting and sockets of system. Weakening of electric connections and bad contact with weight can be the cause of many malfunctions which are observed as serious refusals. 2. Check degree of state of charge of the battery. Normal operation of sensors and actuation mechanisms of a dosage of fuel depends on supply voltage. 3. Check a condition of the air filter, pollution of the filtering element can be the cause of essential deterioration in operational indicators including profitability (see subsection 2.7.2). 4. If the fused safety lock is found, then replace it and check work of the corresponding chain. If the safety lock fuses again, then find the wire closed on weight in conducting. 5. Check tightness of the channel of an air duct from the filter to an inlet collector. Existence of a suction of air in an air duct leads to excessive impoverishment of mix. Check also a condition of the vacuum hoses connected to an inlet collector. 6. Remove an air duct from the camera of a butterfly valve and check existence of deposits of a deposit and resinous deposits. At pollution wash out the case an aerosol cleaner of the carburetor and clean a toothbrush (at first be convinced, having read the instruction on a barrel that the cleaner is harmless to sensors of oxygen and catalytic converter). 7. On the working engine apply a stethoscope to each of nozzles and listen to the characteristic clicks indicating normal work of nozzles. 8. If the stethoscope is absent, then use the long screw-driver. Apply the termination of the screw-driver to a nozzle, and bring closer an ear to the handle. 9. If listening yields doubtful results, then buy the special light indicator of nozzles and insert it into the nozzle socket. Start the engine and be convinced that on each socket of a nozzle light flashes. The size of tension given on nozzles is so checked. 10. On the idle engine disconnect sockets from nozzles and check resistance of each nozzle. Resistance of each nozzle has to be within 13,4–14,2 Ohms. If resistance differs, then replace a nozzle. 11. Other checks should be carried out in service of car service, or in a specialized workshop as malfunction of the control unit can be the cause of abnormal work of system.