1996 F350 4x4 crew cab long bed, straight pipe exhaust, tymar DP, Napa 6637 filter, new fuel filter, shimmed FPR, TWildman 4-pos chip, replaced pass side valve cover gasket, injector harness, and all glow plugs (all VC gasket plugs dont seem to be burnt either), new CPS. I have done other small mods but i dont think they would effect the idle. it was doing this before i installed the chip as well

I have been having a very annoying stutter or rough idle with my truck lately. i have scoured this site and haven't come up with anything that pertains to my certain situation.

my question involves 2 sensors... the ICP and the IPR (i think thats it). would either of these cause erratic or rough idle if they were bad?

to check i unplugged the ICP and i get a check engine light but it *SEEMS* to run better. i have only had time to test it once so i am not sure if that helped any.

the IPR is between the HPOP and fuel bowl correct?

 

If the o-rings are bad on the IPR (located on the back side of the HPOP Res.) it could be letting oil by and not keeping constant pressure supplied to the injectors. If you unplug the IPR it goes to a default setting, instead of reading the actual oil pressure. If it runs better unplugged, I would recommend changing the o-rings.

Also the FPR shim has been known "on some trucks" to make the idle rough.

 

ok kool, thanx for the response man!

if i were to pull the IPR to check the o-rings is there anything special i need to know about? or can i just pull it real quick and check?

i'll pull the BB tonight after work/skool and see if that makes a difference!

-cutts-

 

plowhand i think means icp will go into a default setting. if you unplug ipr i am pretty sure truck wont run.
here is what i have learned about icp's. if your truck runs like crap and then you unplug it. you drive it and it runs better........time for a new icp.

i got one off ebay for around 50 bucks i think.

if you pull the ipr really quick without draining hpop reservoir first well you will flood the valley. and if your gonna pull it you might as well buy the new orings first.