95 F250 5.0 V8 4wd. It idles up and down. almost dies. What are the usual culprits?

 

Sticking IAC, vacuum leaks, bad TPS.

 

I would suspect a vac leak some where first, and hit all the vac lines, good possibility if they are original to the truck, they are at least 16 years of age or more, one is cracked some where or broken off, no need to throw parts at it unless you need to

 

I had previously searched for this problem on the forum. Some got so involved that I got a little lost. I will search for vacuum leaks first as advised since this is cheapest.
Many thanks guys

 

You can remove the IAC, inspect, then clesn if necessary. Use carb cleaner on the plunger, be careful to not get any in the solenoid.

A somewhat common source of a vacuum leak is a worn throttle body shaft.

Sometimes easier to plug all vacuum lines except the MAP sensor. If the surge remains the sources are narrowed to a smaller group.