It is probably already mentioned, but I had a similar issues with my TPS, IAC, MAFS, CPS, and the VCC would cause stalling when coming to a stop throughout various jeeps. I also had low fuel pressure that would cause wonky idle and finally dying before the pump finally took a crap '98 Ram. With my XJ the TPS went bad with no code. I would start by making sure all plugs, wires, caps etc. are correct and tight, My 02 died and ran horribly when the plug rail was installed incorrectly. Next I would verify all injectors are firing, may be worth your time running some seafoam through the gas and brake booster hose. If all is good there, I would move onto checking if the vehicle is getting enough fuel through the pressure lines. Next I would verify the vehicle is breathing properly, especially if it is up in the hills, take a gander at the air filter housing and the throttle body to make sure nothing is causing restrictions. If you still are having problems then it may be worth doing a pressure test or block test before pulling the head and see if you have a blown gasket.
I would almost bet it is going to be a fuel delivery or sensor issue. I will say from experience to double check all sensors recieved for correct part number and engine size. I have, on two occasions, been given wrong sensors, 94 xj was given a 2.5l TPS and on my 02 I was give the 2.5l MAF, these will cause your symptoms as well. I usually will either call another store to make sure my parts match, or google them. I am not sure if you mentioned, but are you getting any abnormal noises such as a clatter, knock or anything? or having any mixing of fluids or smoke?