2007 Grand Cherokee WK Factory Service Manual 14 - FUEL SYSTEM

STANDARD PROCEDURE

CLEANING FUEL INJECTORS



NOTE: Before cleaning the injector recesses, seal the injector holes in the injector recesses with the appropriate pin to prevent debris from falling into the recesses and entering the motor.


1. Using a lint-free rag, wipe the cylinder head around the fuel injector.
2. Wipe out injector recesses with a lint-free cloth, then clean with a cylinder brush.
3. Clean the bottom of the cylinder recess with a round brush.
4. Blow out the recess and clean again with a lint-free cloth and cover over.
5. Perform these steps for each injector recess.

NOTE: DO NOT clean the tip of the injector with a wire brush. Use a lint—free cloth.


6. Clean injector body with a wire brush.
7. Clean injector tips with a lint-free cloth.

NOTE: Do Not apply antiseize lubricant to the injector nozzle, apply only to the injector body.


8. Grease injector body with antiseize lubricant.

NOTE: Always replace the seals that seal off the injectors at the cylinder head to the combustion chamber.

INJECTOR CLASSIFICATION

The classification of injectors describes the quantity characteristic of the injector. This will make it possible to match the engine software to the tolerances of the injector within a more narrowly graduated range. Classification can be clearly recognized, and assigned only by means of a scantool.

Classified injectors can be recognized by the six-digit alphanumeric code or part number and identification on the magnetic head. The number corresponds to the classification stage.

These general conditions equally apply if, as a result of replacing an engine, carrying out repairs to the cylinder head etc., the cylinder selective assignment of the injectors or the engine control module assignment may have changed. If proper attention is not paid to the classification on these vehicles driveability and smoking concerns could result.

If an injector(s) is replaced, or if there is any concern that an injector may not be installed in its original location, it is then necessary to assign the classification number to the corresponding cylinder with the scantool in the control module.


INJECTOR CLASSIFICATION PROCEDURE


1. Turn ignition switch “ON”.
2. Using a scantool, select ENGINE then MISCELLANEOUS.
3. Select LEARN INJECTORS.
4. Using the up and down arrows, scroll to the appropriate injector.
5. Using the right and left arrows, set injector to proper classification.
6. Once injectors are classified, cycle ignition to complete.