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96 Jeep Grand Cherokee dies and won't start intermittently

This has been going on for over 2 years, 3 computers and 2 crankshaft sensors among various other parts checked out or replaced. With each new computer replacement, it will work for up to about 3000 miles and then it starts doing “it” again. I can be driving down the road and all of a sudden it will chug and die. Sometimes it will start, other times it won’t. Sometimes it will start 2 days later and run for a couple of weeks. It seems to get progressively worse. When it starts having these problems, the check guages light comes on and the message light reads “coolant level low” although it isn’t. I have had every wire taken off and check and it always comes back to being the computer. Is something making the computer go bad or am I getting a “batch” of bad computers? This all started a couple of years ago when the computer and crankshaft sensor were replaced for other reasons, and soon after this started happening. Because it was a new computer, they didn’t think it could be at fault. I’ve had it to 3 different shops, 1 guy kept it for a month driving it to try to diagnose it when it actually happened. They can’t get any definitive read when they hook it up to diagnostics. Any solution greatly appreciated!

It would be good to know if the ignition system is working when the trouble happens. I assume it doesn’t work. It would also be interesting to know if the replaced PCMs worked in another car. I have a hunch they would and are being replaced needlessly.

I suspect there is a wire connection problem causing the trouble, as a guess it may be near the PCM. The warning for the gauges and low coolant level may be a good clue to the riddle. I would start the hunt by checking the power lead to those areas. There may be a grounding problem also but I think that is less likely. Do the gauges show a change when the trouble happens? If so, that would really cinch it as the trouble I think.