Nissan Patrol, Ford Maverick

1988-1997 of release

Repair and car operation

Systems of injection of fuel (EFI) and engine management - models of 4.2 l of release after 1992.

General information

On an accompanying illustration the type of an impellent compartment of model of 4.2 l of EFI with an arrangement of various components of power supply systems and engine management is presented.

Since October, 1994 manufacturers refused use of the electromagnetic valve of a regulator of pressure.

The control system of the engine in this Management is called an electronic control system of fuel (ECCS) ignition. The system exercises administration at the same time ignition and fuel injection.

The central ECCS component is the control unit (ECU) being the microprocessor. ECU operates installation of a corner of an advancing of ignition and amount of injected fuel on the basis of the signals received by it from various sensors. At registration of changes of load of the engine, numbers of turns, speeds of movement of the car, temperatures of cooling liquid, the provision of a butterfly valve, a choice of transfer, temperature of soaked-up air and composition of the fulfilled ECU gases gives out commands for the corresponding correction of a corner of an advancing of ignition and time of opening of injectors of fuel for the purpose of receiving the maximum return from the engine in the current conditions.

At registration of a repeating abnormal signal of ECU remembers a contour of a source of a signal and writes down it in the memory block in the form of a digital code that essentially facilitates procedure of diagnostics of malfunctions of system. At detection of malfunction of the sensor of an angle of rotation of the distributor or global internal refusal in ECU influencing overall performance of the engine there is an inclusion of a control lamp “Check the engine” on the dashboard, at the same time with which ECU includes system of emergency functioning that allows to continue car operation with limited possibilities of the engine before elimination of a cause of failure. Reading of codes of malfunctions from memory of ECU in a workshop of dealer office of the manufacturing company of the car will facilitate diagnostics of causes of failure.

The structure of high-energy system of ignition includes the distributor, a powerful key of the target cascade, the coil of ignition and connecting electroconducting.

The distributor carries out double function. In the first, it carries out giving of secondary tension of the coil on spark plugs. In the second, the distributor delivers to ECU информациею about turns of the engine and position of pistons. This information is removed by the sensor of an angle of rotation located in the distributor.
As for installation of a corner of an advancing of ignition the control system of the engine answers, the distributor is not equipped neither vacuum, nor centrifugal with proof-readers of the moment of ignition.

The powerful key of the target cascade is fixed near the ignition coil. Also carries out function of interruption of primary contour, joining at the command of ECU. Thus in a secondary contour the high voltage is induced.

The coil of ignition has the special design meeting special requirements of electronic system of ignition and should be replaced only on similar to.

A food of the engine is provided by electronic system of multiitem injection of fuel. The system provides fuel injection in a stream of soaked-up air in inlet ports of a head of cylinders. Further the air and fuel mix moves in combustion chambers via inlet valves.

Supply of fuel to injectors is provided by the high-pressure head pump of pogruzhny type fixed in a fuel tank. For the purpose of suppression of pulsations of the fuel caused by operation of injectors and own functioning, the pump is equipped with a special damper.

Pressure in a power supply system is supported at level of 235 ÷ 294 kPas, depending on pressure in the pipeline. Management of pressure of fuel carries out the special regulator which has been built in in the fuel highway. When the engine does not work, fuel on a site between injectors and a gasoline pump remains under pressure thanks to installation in the pump of the unilateral valve.

The amount of injected fuel is defined by time of opening of injectors. Duration of an interval of opening of injectors is defined by ECU on the basis of the data received from the sensor of an angle of rotation of the distributor and a measuring instrument of an air stream. Base duration of injection then can be corrected on the basis of information of the sensor of temperature of cooling liquid (CTS), sensors switches of a butterfly valve and permission of start, the sensor of speed of movement of the car, the provision of a key in the lock of ignition and l-probe data for the purpose of receiving from the engine of the maximum return in specific conditions and the current mode of operation.

The air regulator provides increase of turns of idling of the engine in the course of its warming up at the expense of a perepuskaniye of an air stream bypassing a butterfly valve. Work of an air regulator the bimetallic plate which is curving at warming up by an electric current operates. Being curved, the bimetallic spring rotates a disk in an air regulator that leads to gradual reduction of a stream of air up to its full perekryvaniye.

The block of adjustment of air of the idling (IAA), established in a back part of the delivery chamber of an air path, operates turns of idling of the engine. The block is equipped with the screw of adjustment of turns, the valve of additional air and the device of compensation of turns of fast idling (FICD).

The AAS valve provides supply of additional air bypassing a butterfly valve, thereby supporting idling turns at increase of loads of the engine. The FICD device operates similar to the AAS valve, but serves specially for compensation of increase of the loading connected with turning on of the conditioner of air.
The case of a throttle is located on the delivery chamber of an air path and operates amount of the air which is soaked up in the engine depending on the provision of a pedal of gas.

Efficiency of action of a control system of the engine depends on accuracy of information arriving on ECU, about volume of an operated stream of air from a measuring instrument of an air stream. Thus, special importance is gained by purity, quality of a condition and reliability of fastening of all air, fuel and electric connections.