97 super duty running bad cold

[JMF350]

On cold start up, it has what sounds like a dead miss, than after about 8-9 miles, it's like you flip a switch, and it runs great. The high pressure oil stays the same, ruling out a possible "O-ring", BTW.... it has re-man injectors in it, about 1 month old. Before they were put in, it had misses all the time. No codes present. Any ideas?

 

[arrowstrap]

check UVC wiring harness. could be making / breaking connection with vibration and temp. check wiring connection to injectors. wiggle each one with motor running & see if there is a change.

 

[Crumm]

I would point at the IPR.

 

[JMF350]

UVC gasket and harness are new. IPR runs about 15-17% at idle... 35-36% at 65 MPH, which is around 2600 RPM's. It doesn't change when the miss goes away.

 

[arrowstrap]

have you replaced the CPS yet?

 

[JMF350]

Yes..... that took care of another problem it had

 

[arrowstrap]

i'd try removing the superchip program, returning it to stock, then reloading it. i have had a few questionable acts from my motor with performance or tow setting VIA superchip. unloading the program has made my problems vanish for eternity...

 

[JMF350]

The truck in question is not mine. It is completely stock with the acception of a straight pipe. BTW... the new injectors, GP's, and UVC gaskets and harness is from Pensecloa diesel... on the the super kits. When I first installed all hardware, it had 3 dead cylinders. Drove the heck out of it for 50+ miles, pretty sure it wasn't air in the system. Switched 2 injectors on one side, with the other 2 that weren't missing, miss followed the injectors. Got 3 replacements, and have it down to one now. Of coarse, after they received the injectors back, they checked them, all OK, even put them in another truck, with no problem Whatever. Haven't heard alot of good things about them........

 

[95_stroker]

Have you done a compression test yet?