92 Roadmaster Hesitation Problem

I have a severe hestiation problem with my 92 RM 172,000 miles. When at idle in driveway, depressing accelerator I get a definite flat spot, seemingly a vacuum problem. When out on road at cruising speeds it seems as the engine gets warmer its nearly impossible to keep it running, hesitates, loss of power. The service light is not on so I have not checked for any service codes. Any ideas on what can cause this type of hesitation and virtual power loss?

Sounds fuel related to me, have you checked fuel pressure? You might have a bad fuel pressure regulator.

HOTZ28 thanks for your response and here is the continuing saga. Although I never checked the fuel pressure, I discovered I had 2 bad plug wires. Changed them out started the car and took it for a test drive - perfect. The car was purring like a kitten. Took it out on the road about a 60 mile round trip around mile 40 it started to hesitate and eventually lost power. It is now sitting at a friends farm about 5 miles from home and it will not start and I am not sure if fuel or spark related. Car has a new starter and battery. I now have a code 23 MAT sensor from the OBD I using the paper clip trick. Any further help putting this puzzle together would be appreciated.

Code 23 was probably set in response to the engine stalling, but would not likely be the cause of stalling. You can check the MAT sensor, wiring, and connectors for a possible open circuit, or simply replace the MAT sensor, but this will not solve the problem. Check for spark & fuel!

I disconnected/re-connected the battery and started the car this morning and it ran for 5 minutes and quit. Code 23 has apparently reset itself as the sevice engine light is not on while the car is running. Going back to Friday night it would not start, even with ether. Now it will start almost every time but run for anywhere from 10 seconds to 2 minutes. Then it simply cuts off. While it is running, it is running correctly - no miss, smooth. At this point I am looking for the path of the greatest percentage to pursue between fuel flow and spark.

Apparently, if it does not start using starting fluid, you do not have spark. Things to check are the distributor cap, rotor, ignition control module. Also, take a close look at the carbon button inside & top of the distributor cap & be sure it is not worn down.