High Idle

i was given the van dont know much about it, its not inspected so i cant drive it
its a 1994 with a 3.8 no ses lights but the airbag light is on
the first problem i need to fix is the high idle
it starts right up then i goes to about 2000 2500 rmp and stays around that inless i put in in gear
these are whats been changed so far
plugs and wires
throttle position sensor
plenum gasket
egr cleaned and new gasket
im lost and i dont want to guess and replace things so i need help

...veriify throttle linkage....to begin with...`verify if throttle valve closes to stop; is it possible new TPS improperly rigged and prevents throttle closure? (simple things first; that works most of the time).

Too bad you cannot drive because there are several types of info that would be relevant, FOr example, failed TPS would inhibit 4th, TCC and cruise...and might cause high idle.
www.avigex.ca/xport/dtc22.jpg '94 OBD1 1/2 is not that easy to retreive codes.
Failed TPS (would pop a code though) and leaky intake gasket are possibilities, as well as disconnected vacuum ports like power brake, potential suspects since work was done around that.

Were all replacements you mention done at same time and not driven after that?

i sprayed carb cleaner on all the vac hoses to look for a vac leak and found nothing, i dont have time to check the other things right now
im not sure about the work thats been done , i didn't do it, i do know it was done because of the high idle and he did drive it some with it idleing like this. he also said that around 40 mph it would lose power and shake

wow i forgot about this post.....i unpluged the TPS and it idles at 1000 rmp now, does that mean its bad? it still runs rough when i step on the gas it doesn't want to move and when i floor it and hold it there it goes to 3500 rmp then down to 3000rmp and it keeps going up and down

,, when i floor it and hold it there it goes to 3500 rmp then down to 3000rmp and it keeps going up and down
Normal..this is the RPM limiter acting so pistons do not fly out into orbit.
Without TPS, il will not respond to rapid throttle changes.
Measure TPS resistance between one side and center connector. Resistance should vary smoothly from a few hundreds ohms to several thousnds without misses or jumps as one depresses throttle.

the ohms are all over the place..is that a bad tps?
i talked to a guy that said it could be the computer. it that posible?

If reistance measurement is other than a shooth unbroken increase from minium to max as throttle is slowly depressed, the tps resistance track is dirty/scratched. I would replace it. If it is recent, as you say you already changed it, is warantee still valid? .