97 psd rough idle poor throttle response Help!!

[yz13]

ive got a 97 f250 and i was going to church sunday mornin and i get to the end of my road and my truck starts idling extremely rough anywhere from 4 to 800rpms and i go to give it some throttle but it wont do anything till im 3/4 throttle. In the last yr ive put a new tps, cps sensors in it and I just put new d66 turbo, stage 2 injectors, clutch, and a tw chip on it along with new vavle cover gaskets and pigtails and such. It ran amazing the night before but now im stumped. and i need to get this resolved by the end of the week because i start college All help is much appreciated.

Im wondering if it isnt the icp sensor but im not sure. I ran the codes and all that showed up is p0603 and p0470

[BigFuel]

First code is the danger code unless your running a chip. Faulty PCM, not cheap. 470 is the exhaust back pressure sensor. Will the truck start? Will it run at idle?

[yz13]

i have a tony wildman 6 position chip in it that plugs into the pcm and yes itll start and run fine for a couple of minutes but then itll start acting up. Itll run at idle but it is so rough that i just turn it off because it seems pretty hard on the motor. Also when it starts acting up the throttle starts having very poor responsivness

[BigFuel]

Sorry, had this whole thing typed up and hit post just as I I reread your sig and you have already gutted your EBPV. Still thinking but pull the chip and go for a drive. See if things change. Maybe the chip started backing out of the PCM

[BigFuel]

Whats your fuel pressure at idle. It'll mess it up but you can put a tire gauge (dial type) on the fuel bowls schrader valve and get an approx. answer. Also pull the plug off the ICP and see what the truck does at idle.

[yz13]

ok i give all that a try. My fuel pressure is right around 58 to 60. Thanks alot for the tips

[BigFuel]

No worries. Fuels good. Pulling the ICP plug might tell us something about the HPOP. When was the CPS changed last? What do the Gauges read when it does this? When was the last fuel filter swapped? Did you clean the FPR screen in the last 6 months?

[yz13]

It started idling horribly in the driveway and actually died so i unpluged the icp sensor and it ran just fine so bad icp sensor then?? In febraury the cps went bad so it got a new one and will i was at it i cleaned the fpr screen and changed the fuel filter. Truck also see regular oil change every 5000 miles. im thinkin the its the icp sensor since it runs fine unpluged.

[BigFuel]

ICP's are expensive. Try this first: