Apps?
 

I have heard mention of resetting the APPS. What does this do? ANd how do you do it?

here ya go.
Tools: Digital Volt Meter, T-20 Torx bit, #1 phillips, 10mm socket

With the key on, engine off you need to probe the APPS wire to see where the voltage is currently set at.
The best location to probe the wire is on the PCM (Power Control Module) which is located on the passenger firewall behind the air intake.
You want the C1 connector, this is the connector closest to the engine
You want the orange wire with a dark blue tracer which is pin #23
Voltage should be somewhere around 0.5 volts,
At this point the voltage reading does not matter, it just has to be accurately written down for later reference
TURN THE IGNITION OFF ON THE TRUCK

Remove the black plastic cover off of your APPS. There are two plastic screws. One on the top and one on the front facing the radiator. It takes a little prying to pull it off.

Undo the 6-10mm bolts that hold the bracketru in place but DO NOT REMOVE THE CABLES!!

You will notice the APPS is on the back of the bracketry that you just removed, it is held in place by 2-T20 torx bit screws. These screws have a little bit of locktite on them so make sure you have a good socket and gently give a little tap with a hammer before attempting to loosen. Be very careful because these screws strip VERY easily and you only get one shot at them (VERY VERY VERY IMPORTANT; They are VERY tight).

On the APPS you will find a white tag that gives you the information on what the APPS voltage should be.
After loosening the screws (do not remove) you can rotate the APPS clockwise or counter clockwise to get the adjustment (towards the front of the truck increases voltage and towards the rear of the truck decreases voltage)
The reading you took at the beginning of the process on pin #23 should match the white tag on your APPS. If it doesn't then adjust accordingly.

Resetting the APPS causes the ECM to 're-learn' where the throttle is at all times when something happens to cause the ECM to not understand what the APPS is telling it like a dirty spot or something like that. What you do is disconnect BOTH batteries (yes you will need to reprogram your radio), turn the key on and wait for atleast 10 minutes, then turn the key off and hook up the batteries. Once that is done turn the key on but don't start it yet. SLOWLY and steadily push the throttle to the floor and SLOWLY and steadily release it. Turn the key off and then you can start it. You have now re-set the APPS. Normally when you need to do this your APPS is in the process of failing but you bought some more time for it.
Tom

MnTom am I to do this after above mentioned or is this another way? Thanks for the replies.

Just do as Tom advised and see if that makes a difference. His is the commonly accepted method for resetting the APPS.

If you want the most accurate way do it the way that rbratby says. The way I said is the easiest way.