GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Notice: Use care in removing the fuel injectors in order to prevent damage to the fuel injector electrical connector pins or the fuel injector nozzles. Do not immerse the fuel injector in any type of cleaner. The fuel injector is an electrical component and may be damaged by this cleaning method.

Important: 

   • The Denso fuel injectors that are installed in the 5.3L (L59) E85 application will not have O-rings and retaining clips serviced separately. Therefore, the fuel injectors will be replaced whenever an O-ring or clips needs to be replaced.
   • The engine oil may be contaminated with fuel if the fuel injectors are leaking.


    Object Number: 350543  Size: SH
  1. Remove the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
  2. Remove the fuel injector retainer clip (19).
  3. Remove the fuel injector (17).

  4. Object Number: 351185  Size: SH
  5. Discard the injector retainer clip (1).
  6. Remove and discard the fuel injector O-ring seals (2, 4) from the injector.

Installation Procedure

Important: When ordering new fuel injectors, you must order the correct injector for the application being serviced.


    Object Number: 351196  Size: SH
  1. The fuel injector (1) is stamped with a part number identification (2). A four-digit build date code (3), which indicates the month (4), day (5), year (6), and the shift (7) that built the fuel injector.

  2. Object Number: 351185  Size: SH
  3. Lubricate the NEW fuel injector O-ring seals (2, 4) with clean engine oil.
  4. Install the NEW injector O-ring seals onto the fuel injector.
  5. Install a NEW retainer clip (1) onto the fuel injector.

  6. Object Number: 350543  Size: SH
  7. Install the fuel injector (17) into the fuel rail injector socket with the electrical connector facing outward. The retainer clip (19) locks onto a flange on the fuel rail injector socket.
  8. Install the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .