I know I will get flamed for this but I am at the end of my rope.
98 tj 4.0 at- I hit the gas, the tranny kicked down and the engine backfired and died when I tried to pass a truck on the highway, when I got to the side of the road it started right back up. Since then I think I have fixed that issue but created a new one. Now it will run fine for a little while and then it feels like its cutting out or trying to shut off. If I mash the gas it runs good but if I try to idle or drive normal it acts up. It usually starts fine but when I try to back out of the drive it tries to die, runs very eradic and kicks the rpm's up to 1500 and continues to try and cut out but rarely ever dies. I have the code read each time and it gives me various TPS problems. I am on my 4th TPS in a week, I have replaced the MAP sensor, IAC, crank pos sensor, coil, cap and rotor, plug wires, cleaned the throttle body, checked the air filter, checked for vacum leaks(no surging, sounds and feels like its losing electric power, unlike the surging from a vacum leak or loss of fuel). Any ideas? Go ahead and flame away but tell me what I might check next.

If you keep getting TPS related problems then maybe it's not the TPS at all but the wiring that goes to it? Check for cracked insulation or corroded wiring. If the circuit cannot carry current the ECM is going to get false readings.

Update: checked the TPS wiring, looks good to me so I sprayed the hell out of the throttle body, this seems to have helped so far, now I only notice a little surging but I am sure other symptoms will soon come back.
While I was checking the starter wiring and grounds I noticed the exhaust manifold is cracked around the weld where the to pipes go in to one, before the collector. With the leak would it mess up the o2 sensor reading that would cause surging?