Jeep Grand Cherokee

1993-1999 of release

Repair and car operation



Jeep Grandee Cheroki
+ Jeep Grand Cherokee brand Cars
+ Settings and routine maintenance
+ Ryadny six-cylinder engine
+ V8 Engine
+ Procedures of the general and major maintenance of the engine
+ Systems of cooling, 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 a fuel tank
   Cleaning and repair of a 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 an air purifier
   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 a 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 operation receptions
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Check of pressure of fuel and functioning of the fuel pump

See the prevention at the beginning of the Section Procedure of dumping of pressure of fuel (the description of procedure of dumping of pressure of fuel see in the same place).


Models of 1995 вып. are not equipped usual vacuum type with a regulator of pressure of fuel. Here the regulator is built in in the fuel pump. In case of the problems connected with pressure of fuel replace entirely assembly of the fuel pump/block of the sensor.

Primary check

If there are suspicions on deterioration of supply of fuel, first of all check fuel lines on existence of signs of leaks.

Check of functioning of the fuel pump

On all models the fuel pump is located in a fuel tank (see. Section Removal and installation of the fuel pump).


 PERFORMANCE ORDER

  1. Cock the parking brake and ask the assistant to turn the ignition key in the situation ON. At this time listen to published by the pump in a fuel tank to sounds. It should be the hum, lasting about 2 seconds.
  2. Start the engine. Now hum should become continuous (though he and will need to be caught because of the working engine). If no sounds are present, is faulty either the pump, or its relay, or the relay of a contour of automatic shutdown of supply of fuel (ASD) (pass to item 1).

Pressure check

 PERFORMANCE ORDER

  1. Dump pressure of fuel (The section Procedure of dumping of pressure of fuel).
  2. Uncover the union of check of pressure of the fuel located on the fuel highway and connect to the union a manometer.
  1. Connect a manometer to the fuel highway and consider its indications at the engine working at single turns (the model with the engine in volume of 5.2 l is shown).
Carrying out check of pressure of fuel on the models equipped with the engine in volume of 4.0 l.
  1. Start the engine and consider manometer indications, having compared them to data of Specifications. Now disconnect a vacuum hose from a regulator of pressure of fuel. Again at the engine working at single turns take readings of the device - it again should meet the corresponding requirements. Connect a hose into place.

Models of 1995 вып. are equipped built in in the block of the fuel pump/sensor of level with a regulator of pressure of fuel, there is a possibility of check of only adjusted pressure of fuel.


Models of 1995 вып. are equipped with the regulator of pressure of fuel built in in the fuel pump.

  1. If results of measurement of pressure of fuel do not meet requirements of Specifications, act as follows:
    • If the result of measurements meets the requirements of Specifications at connected to a pressure regulator a vacuum hose, however leaves out of admissible limits at the disconnected hose, check depression existence in a hose. If depression is present, replace a regulator (The section Check of serviceability and replacement of a regulator of pressure of fuel). If depression is not fixed, check a hose on existence of breaks and obstruction.
    • If pressure exceeds admissible value check passableness of a hose (or tubes of return of fuel). If passableness is not broken, replace a pressure regulator (The section Check of serviceability and replacement of a regulator of pressure of fuel).
    • If the measured pressure is lower than an admissible limit, do the following:
    • Make sure that the fuel filter is not hammered.
    • Whether
    • check it is overwound and whether the fuel hose between a fuel tank and the fuel highway is blocked.
    • Check serviceability of functioning of a regulator of pressure of fuel.
    • Check fuel lines on existence of signs of leaks.
  2. If any of refusals listed above components are not found, check serviceability of a condition of the fuel pump.

Components of a regulator of pressure of fuel

 PERFORMANCE ORDER

  1. Connect the vacuum pump to a regulator of pressure of fuel. Consider indications of a manometer without creating depression on a regulator and at depression. About increase in depth of depression pressure of fuel should fall. Compare results of measurements to data of Specifications.

Models of 1995 вып. are equipped built in in the block of the fuel pump/sensor of level with a regulator of pressure of fuel (see an illustration). Thus, there is a possibility of check of only adjusted pressure.


  1. Connect the vacuum pump to a regulator of pressure of fuel and measure pressure of fuel at first without creating depression.

... and then having created it - in the presence of depression pressure should fall.

  1. Connect a vacuum hose to a regulator and check pressure of fuel at the engine working on idling, compare results of measurements to requirements of Specifications. Disconnect a hose and repeat check - pressure should jump up to the maximum admissible value right after a hose detachment. If pressure on single turns is too high (at the disconnected hose), connect to a hose the vacuum gage and measure depth of depression in it.
  2. If pressure of fuel is too LOW, press the line of return of fuel and track change of indications of a manometer. If pressure did not increase, or the fuel pump is faulty, or passableness of the line of supply of fuel is broken. If pressure jumped up, replace a regulator of pressure of fuel (The section Check of serviceability and replacement of a regulator of pressure of fuel).

It is required to make special rubber inserts between the fuel highway and the returnable line as steel metal lines cannot be pressed for the purpose of performance of this check.

  1. If the indication of a manometer too highly, disconnect the line of return of fuel and try to blow it for passableness check. If passableness of the line is not broken, replace a regulator of pressure of fuel (The section Check of serviceability and replacement of a regulator of pressure of fuel).

Check of a condition of the fuel pump

 PERFORMANCE ORDER

  1. In case of problems with functioning of the fuel pump first of all check the fact of its inclusion (see item 1).
  2. If the pump does not turn on, (sounds are absent), pass to performance of procedures of the following item.
  3. Disunite the electric socket of the fuel pump and directly connect to its plugs tension of the battery (see an illustration below). The pump should turn on.
  1. By means of wires from a set for car start from an auxiliary source connect the positive plug of the battery to the plug of an orange-black wire of the socket of the pump, and the negative plug - to the plug of a black wire of the socket and listen to the sounds speaking about turning on of the pump (the model with the engine in volume of 5.2 l is shown).
  1. Make sure available tension of the battery on plugs of a feeding half of the socket of the pump at the included ignition (a key of the situation ON). If tension is present, replace the pump (The section Cleaning and repair of a fuel tank - the general information). If tension is not present, check a condition of the main relays.

Check of the main relays

For complete check of the fuel pump should be checked both the relay of automatic shutdown of supply of fuel (ASD), and the pump relay. Checks of both relays are made according to the similar scheme.

Scheme of an electric chain of system of injection of fuel of models of 1995 вып., equipped the engine in volume of 5.2 l (the scheme of other models is similar)


 PERFORMANCE ORDER

  1. For relay check, take it from the nest in an impellent compartment.
  1. Find the ASD relay (shooter) and the relay of the fuel pump in an impellent compartment.
  1. Take the relay from the nest and make sure available tension of the battery on nest plugs at the included ignition.
  1. Check supply voltage existence on plugs of a nest of the ASD relay.
  1. If tension is absent, check a pump safety lock. If tension is absent and on a safety lock, check a condition of an electric contour of the pump.
  2. Connect positive щуп an ohmmeter to the plug 86, and negative - to the plug 85 and measure resistance. It should equal about 75 Ohm.
  1. Measure resistance between plugs 86 and 85; it should equal about 75 Ohm.
  1. Connect positive щуп an ohmmeter to the plug 30, and negative - to the plug 87А and again measure resistance. The ohmmeter should show conductivity (zero resistance).
  1. Also measure resistance between plugs 30 and 87А; conductivity should take place.
  1. Connect positive щуп an ohmmeter to the plug 30, and negative - the plug 87. Conductivity should be absent.
  2. Submit tension of the battery on the plug 86 and earth the plug 85. Whether check takes thus a place conductivity between plugs 87 and 30. If is not present, replace the relay.