Ok My friend just got a 95 F250 2wd with 107,000. Has a 6637 and super chip programer on proformance mode. He was was driving home from work the other day and his truck started chug. It chugs hard at an idle. It will has power but not runing 100%. He can still drive it. Told him not to till we get it figured out. No check engine light, Oil changed 3 weeks ago with 15-40wt rotella, also has a new fuel filter. I checked the fuel psi today and have 60psi. So I'm not sure where to look from here, Hoping someone can give me some input? Hpop? injectors?

 

It's always best to start small on things like this. Sounds like filters and oil are fairly new so thats one thing to check off the list. You menetioned HPOP, but they do not tend to act like this when they start to get weak (It's usually during load situations but still drivable).

I'd make sure that the undercover valve cover harnesses are all good and not melted. If they all look good I would inspect the ICP harness and do R&R on the IPR.

Just some things to start with...

 

Thanks Farm69 What does IPR mean again?

 

try this post
https://www.ford-trucks.com/forums/9...ome-apart.html