Originally Posted by 95powersmoker
If it runs the same unplugged as with it plugged, it is doing its job...
Actually, that's not true.
If it runs the same while unplugged, then that means that the truck is already running on the "default" IPR mapping.
At idle on stock tuning, there should be about 540 or so PSI of injection pressure. Pressure should rise smoothly depending on load. Default values due to a bad sensor or wiring harness will put the idle PSI at about 725 and you will DEFINITELY hear a difference in the way the truck sounds at idle. Also, the ICP will NOT rise smoothly with load.