OK, I'm new and appologize for the lengthy thread. But at this point I'm baffled and can use any help available.

2003 F-250, 112,500 miles, 7.3L, Auto, Crew Cab, 4X4, S&B Intake Kit, Stock Exhaust, Diablo Sport Predator U7170 60HP Tune from 2004. No updates on tune since bought U7170 new in 2004. Well maintained. Only repair work in 9 years was CPS change in Feb 2006 before recall notice and new Optima Batteries.

A few days ago, on my way home (20 miles), the truck stumbled for 1-2 seconds and the CEL came on. Ran fine the rest of the way home. 1/4 tank of fuel. Checked codes with U7170 when I got home and got P1280. Cleared code and forgot about it. Few days later, first time to drive it after, headed to town (15 miles). Got half way and CEL on again and stumbling bad with very little power. Turned around and made it 3 miles before dead on the side of the road. Would not refire but turned over fine. 1/8 Tank of fuel but no fuel light yet. Had AAA tow it home. Once home checked codes again and P1280 was the only one. Checked online and found what P1280 was (ICP Sensor). Bought a new one from Ford ($190). Ouch. Changed it out. Truck started up, but ran rough and no codes. Headed to gas station for fuel. Made it 1 mile and dead on side of the road again. Cranks but no fire and no CEL. Towed it home with my '75 Bronco (that just didn't look right at all!!! ) Put 5 gallons of fuel in truck from fuel can. Checked codes, none. Truck cranked up but ran rough. Checked diagnostic data from U7170 and couldn't find anything diffinitive. Although I don't know what half of this data is. Next day (today) I removed the tune and put the truck back to stock tune. Truck ran much better and drove it to the gas station with no problems. Filled it up. Drove home and got on it hard a few times. Ran great for a stock tune.

I also have a lot of data that I recorded by hand from the diagnostic on the U7170. Got idle (~700 RPM) data, 2000 RPM in Park data, and 1500 RPM in Drive Brake On not moving data if any of it is useful. It's quite a bit of data (about 75 data points total) and this thread is already getting long. So I won't post it unless asked. Is there a thread or site that explains this data? Diablo Sport isn't very helpful from my past experiences.

I do have a few questions on some of the data. What is Fuel Lvl In? Mine is always 0% Also, what is Fuel Pump Duty Cycle? Mine is always 100% I would think that this would fluxuate with engine load.

Any idea what was/is wrong with my truck? Was all of this just one big coincidence? ICP Sensor, low fuel, 60 HP tune removal? I'm a little "gun shy" to leave town in it until I have a better feel for what was wrong. Why did changing the ICP sensor not correct it until after I filled it with fuel? Did it have air in the lines and couldn't purge it out with out a fuller tank. Should I not run the tank so low anymore? Ran it much lower many many other times. Did removing the tune even make a difference at all or was it a coincidence? Can I put my 60 HP tune back in? It's been in for 7 years with no problems?

Anyway, I'm rather confused and could use any help or advise that you guys have.

Thanks in advance for any help.

 

Sounds like a coincidence, you likely have a cracked duckbill in the tank above the pickup which is why you only noticed the issue below 1/4, then when you checked the codes you found that the ICP sensor has given errors. If you have not done the intank mods, it would be good to do them as they eliminate the duckbill as well as the mixing chamber which are known to clog up. Welcome to guzzle's In-tank Hutch Mod Web Page

 

Yea, I'm starting to think that as well.

What about the diagnostic data? Is there a thread or site that explains this data?

What is Fuel Lvl In? Mine is always 0%
Also, what is Fuel Pump Duty Cycle? Mine is always 100%
I would think that this would fluxuate with engine load.

 

Truck still seems to be running OK.

However, I'm a little disapointed that I didn't get more replys to my questions. Especially about the diagnostic data.

 

I know my Snap-on scanner show's the same data for the Fuel Level and Duty cycle % I just assume that the fuel sender is not monitored by the PCM, might be wrong having studied all the inputs.