Maybe an AC compressor issue? Jeep tries to die

I've been told theres a good chance this issue is my AC compressor.

When i have my heat on and im at an idle, the jeep will cycle and rev up slightly, then suddenly rev down considerably and come very close to dieing, sometimes it does die off, if it doesnt die, it comes back up to normal idle, and this process repeats every 15 seconds or so. this also happens, heat or not, when i shift from drive to park, the second i get into park and let off the brake, it cycles down like that, only once though. there is also a chirping/squeeling, not nearly as intense as a wet or shot serp belt, but its there, varying with throttle.

though when the heat is off, the jeep will not cycle like i mentioned when idling, everything seems fine. why would this happen?

any suggestions? thanks guys

You didn't state if you were in defrost or not. If not, it shouldn't be the AC. Did you hear the AC clutch kick in when the revs dropped?

i dont think so

aaaand no not in defrost, just normal heat

I see by your profile it's a 97...how many miles? I'm assuming 4.0?

1997 w/ 125k 4.0l

There's a really easy way to determine this. Get into the engine compartment and find the electrical terminal on top of the air conditioner's receiver dryer. There's a safety switch there that prevents the compressor from cycling if the refrigerant is low. Pull the terminal off and then try it. This will prevent the compressor from coming on when you run the defroster (or any other time). If your problem goes away, then it's the compressor.