Help! 1996 f350 7.3 5speed 156k
So started when it was cold 2 days ago let it idle and warm up pulled onto the road and it immediately acted as tho it had no gas pedal. pump it a few times doesn't fix it, sounds like it wants to stall but doesnt, it eventually comes back. then happened again the next day after i drove for 1hour then went away now it's happening a lot more. It doesnt die and it can rev really slow up to 1200rpm while its going or if it does it on the highway it will drop my speed to 45mph then go away I can speed back up...
TPS has been ruled out. Put a new fuel filter on. I cleaned the ivs and held it in with a screw driver while pushing pedal that didn't let it Rev, I'm assuming that would mean it is working. I checked oil etc all checks out ok. Only other issues I've had with it is very hard to start when cold haven't had a chance to test glow plugs yet.

 

There is a test procedure some where for testing the pedal.