This MProp/Metering Unit repair kit contains OE replacement parts that are a guaranteed fit. This kit will replace the Fuel Control Valve/MProp/Metering Unit as well as the connecting harness and terminal contacts, which themselves can be the cause of the unit failure (i.e. the original connector vibrates, causing wear which can ultimately lead to a loss of electrical connection and damage to the Metering Unit). Some equipment panels that use SPN or KWP codes, might show the following error codes if this Metering Unit and/or Harness has failed. Possible Codes: SPN: 523615  and/or KWP: 592, 593, 594, 595, 596, 597, 598, 599.  Since the failure of either of these items can lead to premature failure of the Rail Pressure Sensor (RPS) and Pressure Relief Valve (PRV), be sure to verify you do not need to replace your PRV and RPS.