GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Important: If the fuel injectors are leaking, the engine oil may be contaminated with fuel.


    Object Number: 682635  Size: SH
  1. Remove the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
  2. Remove the fuel injector (5) by pushing the locking tab on the fuel rail toward the center of the fuel rail.
  3. Remove the fuel injector upper O-ring (6).
  4. Remove the fuel injector lower O-ring (4).
  5. Discard the injector O-ring seals.

Installation Procedure

Caution: In order to reduce the risk of fire and personal injury that may result from a fuel leak, always install the fuel injector O-rings in the proper position. If the upper and lower O-rings are different colors (black and blue), be sure to install the blue O-ring in the upper position and the black O-ring in the lower position on the fuel injector. The O-rings are the same size but are made of different materials.

Important: 

   • You must use the correct part number when ordering replacement fuel injectors.
   • The fuel injector O-rings should always be replaced whenever the fuel injectors are serviced. Be sure to install the correct O-ring for the fuel injector. If the O-ring is not seated properly, a vacuum leak is possible and poor driveability conditions may occur.


    Object Number: 682635  Size: SH
  1. Lubricate the new upper (6) and lower (4) O-rings with clean engine oil.
  2. Install the new upper and lower injector O-rings on the fuel injector.
  3. Install the fuel injector on to the fuel rail.
  4. Install the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .