If it will run normally at high rpm (like 2000 or higher), but stalls at low engine speed, then your EGR is dead (stuck open). Did you try speeding up the engine when it was running badly? If it is the TPS and you have an auto tranny, then you will likely notice some weird shifting at the wrong times in addition to idle issues. On my 1990 (same Renix ignition system as yours) whenever the TPS went out I got a high rpm idle, not a stall condition. I'm on my third TPS since new. I would suspect the CPS (crankshaft position sensor). If the CPS goes out, you will have no spark but the engine will turn over. It may be an intermittent problem at first, or die completely. Test is to check for spark, and to try the unplug/replug at the connector for the CPS, located on the rear driver's side corner of the engine, above the fuel injectors. The reconnect routine will sometimes get it to start if it is the CPS. How about other electrical stuff on the jeep? Did you have any weird loss of power to guages, lights, or other stuff? If so, then the ignition switch at the bottom of the steering column is burnt out, and loosing connections. Any more clues you can offer would help narrow it down.