So,I am working on a 2003 F250 6.0 manual trans. all stock. 204,000 miles.
I got it not running. Charged the batteries and pulled the 14 codes accumulated by the last people trying to work on it.There were cyl 1,2,5,6,7,8 contrib codes, P0403 and P0405 egr(the egr was unplugged when I got it), P0341 Cam pos., P0500 VSS, P0562 voltage low, P0683 glow plugs, P1378 fuel inj. ctrl., and a P1000. It is on it's second used car lot, no one can fix it and I don't know what they have done.
Cleared the codes, removed, cleaned, replaced the EGR, installed new batteries, and went over the wiring harnesses. I am down to the P1000, an occasional P0405, and random cyl 3, sometimes 2 contrib codes. If I warm it up and clear the codes, I don't get any contrib codes.
I hooked up the Scan Gauge and the ICP is 554-up cranking, starts without any long crank, runs at 644 at an idle, revs up and reads 2404 max. This is sitting in the garage.
The IPR was 14.8 to start off with, running mostly between 29.7 and 38. revving it up.
The FMD is steady 48.0.
I have run the buzz test both warm and cold- sounds good, no faults found.
Have run the KOER and KOEO demand tests, no faults.
There is no smoking.
I have changed the fuel filters.
I have not located an adapter to hook up my fuel pressure gauge.
As it is right now, it starts reasonably well (it's in the 20's here at night). It runs rough until the temp gauge gets to the top of the little thermometer symbol, then it runs better. The turbo sounds like it's operating as expected, nothing weird. Cold it has a rough idle and poor throttle response. Warm it idles well, with an intermittent light "shudder" .
The weirdest thing I find is the fuel pedal, when I rev it up warm, it won't come back to idle right away, takes 10-20 seconds. It also does this shifting. It does not rev up on it's own, and it will stick at any RPM.
I did not find a value for TPS on my datastream on my scan tool (Auto Xray Tech scan 7000)
When I let off the throttle the IPR and HPOP pressure drop.
The truck was hardly driven for the last 7 years (6000 miles).

I have added some Archoil 9100, that smoothed out the warm operation even more, it drives perfectly down the road (300 miles the other day)

I sent the FICM (the guys on the other forum insisted my problem sounds like the logic side of the FICM) to Ed, got it back, no change.

I took a peek at the IPR, it is shiny and clean, the connector is tight and free of oil.

I removed and inspected the throttle pedal, it's seems clean and operational.

It only has the cylinder contrib codes cold, and it is usually only one cylinder, that cylinder changes, first it was 8 a couple of times, then 3, then 2, now 7. I have no idea which injector could be bad and there is no smoke.

I guess the biggie here is to get the throttle to stop sticking. It runs better everyday, but the sticking could be dangerous. The rough running cold cold just be this engines normal. The light shudder at idle goes in 3-5 second increments- light shudder-smooth-light shudder-smooth...

TIA for any ideas!!

 

P0405 is typically a bad EGR valve - caused by a bad coil in the valve

 

The top of the EGR was chipped off where the harness locked (previous work done?) I have stabilized the harness and gotten rid of that code.

 

Had you tried pulling the ICP connector and seeing if it smooths out?

 

^^ disconnect icp sensor. Also pull ipr valve and inspect screen. They both deal with cylinder contribution. The icp monitors ipr and tells ficm what to do

 

I agree with this diagnosis also.

 

Can you pull the ICP connector with it running? Don't I have to remove the FICM and intake and overflow?
I will look into the ICP.
Any ideas on the throttle?
Thanks

 

Reach behind the turbo (to the right of it). Its gunna be tight but pull your sleeves back and you can reach the ipr and icp sensor. Make sure you found the icp sensor and wire connector and you should be able to unclip it with one hand. If the idle and performance doesn't change, plug it back in cuz its gunna set a CEL(check engine light)

 

So, I finally got the truck running reliably. It still has a rough idle cold, but runs great warm.
Ed fixed up the FICM and it still had a rough idle and sticking throttle warm.
The problem with the throttle sticking was a modified pedal. I believe some old school type mechanic bent the top of the pedal, where it makes a "v", to try to make it idle a little higher and stop running rough. The end result was the pedal lost an inch of travel, the computer adjusted for the shorter range of the TPS, the idle stayed the same, but somehow it "confused" the computer and it wouldn't respond when the throttle was released. A new pedal assy from Dorman both fixed the "sticking" (not physically sticking but reading wrong) and made the truck run much better.
Thank everyone for your help!