Random engine stalling/starting problems

[fgard]

2001 LeSabre. 80K. Engine stops dead without any warning. No warning lights, no codes, no pattern or specific interval, no dealer or shop help. Last two times: Cold day, highway speeds, tach dropped to zero simultaneously with loss of power, but I'm sure the engine did not stop that fast -- oil pressure stayed at 65 for about 10 seconds. In every instance, engine will crank normally, but a 2- to 20 minute wait is needed before it will start again. Seems like an ignition problem. Fuel pump checks ok. One time - wiggling the underhood fuse box seemed to solve the problem. I've tried swapping ignition fuses/relays. Always get it started, but there is no pattern to what 'works'.

In the past, I've seen the tach drop to zero several times -- with no engine stoppage. Always works again after next engine start.

Starting Problems: Always starts at home, sometimes won't after a stop elsewhere. Could be after a stop of 5 minutes, or 3 hours. Cranks fine, no start, no clues. After a wait, it starts, runs like nothing was ever wrong.

Any ideas??

[HotZ28]

Typical symptoms of a bad crank position sensor (CKPS) or related wiring to the ICM. I would not discount the ignition control module (ICM) as a possible source. They are both heat sensitive.