1994 grand Cherokee,stalls when stopped in gear.also when moving slow.

Transmission might be fried. One suggestion, did you try putting it in 4WD and trying that? I had a Jeep come in, same thing, wont move, ended up being a blown transfer case. Put it in 4 hi or low, and see if it will go into gear and move. Long shot, but worth a try.

sounds lik ethe torque converter is going bad

simple test
ut the hand brake on and start the car
idling ok --good --apply the foot brake-- idling bad --replace the brake booster
check for other vacuum leaks including transmission actuator hose , dash vent controls hoses

he moved a shift sensor and they are very touchy . I am sending a picture ask him if can tell me what he touched please thank you. I am a self employed mechanic and will send you the link to my pagehttps://www.facebook.com/TedsRepairs

it sounds like your tps sensor might be out of time .(throttle position sensor) you can have this checked at a shop for little or no cost and adjusted for the shop rate of an hour

Check the EGR valve sounds like its bad,or going bad.

fuel filter most likely

torque converter

i would have this fix asap ,could cause internal transm. damage!

have a compression check done, it sounds like the rings on the pistons are wore out