Jeep Grand Cherokee

1993-1999 of release

Repair and operation of the car



Jeep Grand Cherokee
+ Cars of the Jeep Grand Cherokee brand
+ Settings and routine maintenance
+ Line six-cylinder engine
+ V8 engine
+ Procedures of the general and capital repairs of the engine
+ Cooling systems, heating and air conditioning
- Power supply system and production of the fulfilled gases
   General information
   Procedure of dumping of pressure of fuel
   Check of pressure of fuel and functioning of the fuel pump
   Removal and installation of the fuel tank
   Cleaning and repair of the fuel tank - the general information
   Repair and replacement of fuel lines
   Removal and installation of the fuel pump
   Check of serviceability and replacement of the block of the fuel level sensor
   Removal and installation of assembly of the air cleaner
   Replacement of a cable of gas
   System of injection of fuel - the general information
   Check of serviceability of system of injection of fuel
   Serviceability check, removal and installation of the case of a throttle
   Check of serviceability and replacement of the regulator of pressure of fuel
   Serviceability check, removal and installation of injectors of fuel
   Check of functioning and replacement of components of system of stabilization of turns of idling (IAC)
   Service of system of production of the fulfilled gases - the general information
+ System of electric equipment of the engine
+ Systems of decrease in toxicity of the fulfilled gases and engine management
+ Manual box of gear shifting
+ Automatic transmission
+ Transfer case
+ Coupling and transmission line
+ Brake system
+ Suspension bracket and steering
+ Body
+ System of onboard electric equipment
+ Governing bodies and methods of operation



System of injection of fuel - the general information

The system of multipoint injection of fuel (MPFI) consists of three subsystems: air supply, electronic control and supply of fuel. The system in the work uses the module of management of RSM complete with various sensors (the cooler temperature sensor, the sensor of provision of a butterfly valve (TPS), the sensor of absolute pressure in the pipeline (MAR), the oxygen sensor, etc.), on the basis of transferred by which information the module determines the required current composition of air-fuel mix (for specific conditions of functioning of systems of the car).

Arrangement of components of system of injection of fuel of the engine with a capacity of 4.0 l

1 — the MAR Sensor
2 — the Valve of additional air (IAC) (connected to the throttle case)
3 — an air cleaner Casing
4 — the Inlet pipeline
5 — the Test union of pressure of fuel

6 — the Fuel highway
7 — a fuel Injector
8 — the cooler temperature Sensor
9 — Distribution center of power
10 — PCM

Arrangement of components of system of injection of fuel of the engine with a capacity of 5.2 l.

1 — the IAC Motor (it is fixed on the throttle case)
2 — an air cleaner Casing
3 — TPS
4 — the cooler temperature Sensor
5 — the MAR Sensor

6 — the Inlet pipeline
7 — Distribution center of power
8 — PCM
9 — the Distributor (Will thrust under a partition of a motive compartment)

Sistema of injection of fuel and the control system of toxicity of the fulfilled gases and engine management are closely connected among themselves in work and on configuration. Additional information see in the Head Sistemy of decrease in toxicity of the fulfilled gases and engine management.

System of giving (fence) of air

The system consists of the air cleaner, sleeves of an intake of air, the case of a throttle, a control system of turns of idling and the inlet pipeline.

The sensor of provision of a butterfly valve (TPS) is fixed on an axis of the gate and transfers information on the current position of the gate. On the models equipped with the 5.2 l engines the sensor of absolute pressure in the pipeline (MAR) it is installed in the throttle case whereas on models with the 4.0 l engines it is fixed on a partition of a motive compartment.

When the engine works at single turns, the composition of air-fuel mix is controlled by system of stabilization of turns of idling (IAC) which consists of the module of management of RSM and the valve of additional air (IAC). The IAC valve turns on the module (RSM) depending on specific conditions of functioning of the engine (functioning of the conditioner of air, system of hydrostrengthening of a wheel, engine temperature, etc. of a condition). The valve provides adjustment of an air stream behind a butterfly valve and in the inlet pipeline. RSM obtains information from various sensors (the sensor of speed of the car (VSS), the cooler temperature sensor, sensors of the modes of turning on of the conditioner of air and system of hydrostrengthening of a wheel, etc.) and makes adjustment of turns of idling according to requests of the engine and the driver.

Electronic control system

See the Head Sistemy of decrease in toxicity of the fulfilled gases and engine management.

Fuel supply system

The system consists of the following components: fuel pump, fuel pressure regulator, fuel injectors, resistor of an injector and main relays.

The fuel pump is installed linearly and is the pump of the direct drive. Fuel is soaked up via the filter in the pump, passes the line of an anchor through the unilateral valve, comes to the second filter and then moves in injectors. The safety valve serves for prevention of excessive increase of pressure and opens in case of blocking from the digit party, providing free pass of fuel from a high-pressure part of system in low pressure.

The regulator of pressure serves for maintenance of pressure of fuel on injectors the constant set level. Excess fuel comes back to the fuel tank on the returnable line.

Injectors - plunger type with the constant course work from electromagnets. Injectors consist of an electromagnet, a plunger, the needle valve and the case. When giving current on the electromagnet solenoid the needle of the valve rises and fuel under pressure comes to the injector case, and then through a nozzle is injected into the engine. The amount of injectable fuel is defined by the extent of clock pulse of opening of the valve (width of an impulse of the current electromagnet given on the solenoid).

In a type of the fact that it defines intervals of opening and closing of injectors what, in turn, defines composition of air-fuel mix, distribution of the moments of operation of injectors has to be exposed very precisely. For ensuring the most effective operation of injectors the front of impulses of current when giving tension on the solenoid of each of injectors has to be as it is possible for a steep slope. Thus, the quantity of windings of the solenoid is minimized for the purpose of decrease in inductance. However, it leads to decrease in resistance of the solenoid that reduces injector service life. The size of current is limited to the resistor installed in a plait of wires of an injector.

The main relay which is installed near the assembly block of safety locks is the relay of direct inclusion, and contains the relay of food of an electronic control unit and the relay of giving of food on the fuel pump.