missing at idle but not under a load. Ideas??

[YOUNG]

My truck started missing and idling VERY rough a couple days ago for no apparent reason. The missing will smooth right out as soon as you touch the gas pedal and the truck will run great. I had the truck scanned and the dealer said that it had 3 injectors that were miss firing, so I changed them out with new ones but it still does it. The only thing that will make the truck idle better(I know this is going to sound strange) but is to crack open the water drain on the fuel filter housing and let some diesel run out the back instead of returning back to the tank. I know that sounds strange, but it instantly smoothes out.

[ianstew]

try unplugging your ICP and see if that smooths out your idle. if it does your icp is bad...mine idles rough like that and my ICP is to blame......but mine is an OBS.....

[YOUNG]

What and where is the ICP located?

[ianstew]

on mine, its on the drivers side oil rail....towards the froint of the drivers side head......let me see if i can find a pic for ya, i unplugged mine when it was idling and it smoothed right out. http://rides.webshots.com/photo/2290...91838520sSnfJL

[blk99]

also, check the nut on the back of the IPR as well as the plug on it.... sorry i dont have any pictures but just trace the wires from the ICP sensor, down into the valley and you will find it...

[YOUNG]

Thanks for all the help guys, but the truck is still running like crap. I wonder if the cam position sensor could be bad even though it didn't show up bad on the scan???