The fuel injector wire harness connections the fuel injectors on your 6.0L Powerstroke engine to the fuel injector control module (FICM). Overtime the factory wire harness on your F250, F350, F450, F550 or Excursion can develop cracks resulting in rough running conditions, rough idle, hesitation, or even failure to start. This wire harness is a direct replacement for the factory wire harness on your 6.0L Powerstroke engine. The harness retains the factory mounting points and plugs directly into the FICM as well as diesel injectors. Purchase this harness from AA Ignition and save hundreds off dollars.