This is the Sensor located on the firewall of your 6.5 Turbo Diesel. Fits all 94 and newer 6.5TD's in all vehicles. On VIN "S" engines, it is plumbed into the EGR valve circuit to give feedback to the PCM on the EGR position. On VIN "F" engines, it is left with no tubing on the connector port for it to read ambiant barometric pressure and give feedback to the PCM.

When it fails it will give codes 31 or 33, also sometimes codes 32, 44 and 45 for 94-95 vehicles. For 96 and newer the codes are P0405 or P0406, and sometimes P0400, P0401, P0402, and P0404.

This sensor MUST NOT  to be confused with the Boost Sensor located on the intake manifold. Although they appear the same, the plug harness is different and it is calibrated differently internally.

Replace your defective EGR/Baro sensor with only the correct one, calibrated for the 6.5 diesel operation.