2000 F-450 7.3, 6 speed manual,141K

[car94]

Recently replaced 1 Injector and had the other 7 rebuilt also replaced the Glow plugs and the GP Relay. Still will not start if it below 45 degrees, unless I plug it in.
A few days ago it started to Hickup and stalled a couple of times.
Then a couple of days ago I got stuck on a Mud road in northern MO, spun it out and took the truck back to our shop and used our wash wands that clean the under side of the truck.
Today I started the truck after driving for around a Hundred miles without a hick up and it sputtered and started to idle rough when I tried to go it would not rev up under load. I had to slip the clutch to get it moving on flat ground and it would not go over 2500 rpm or over about 40mph downhill. I drove it around 40 miles at around 20 mph average, I bought a new CPS at the local Ford dealer. There mechanic does'nt think its the CPS. Another Diesel Mechanic I know says it is. So does anyone else have any Ideas about either of these problems.
Also it did not smoke at all

[jesilvas]

Check your UVCHs. They supply power to the GPs and injectors and if they are burnt, chaffed, or loose, you'll have problems.

[car94]

Originally Posted by jesilvas

Check your UVCHs. They supply power to the GPs and injectors and if they are burnt, chaffed, or loose, you'll have problems.

What are the UVCH's??

[jesilvas]

The under valve cover harnesses. Do some searches on here and look at some of the tech files or stickies in the 7.3 section and you should find out about them.