I’m pulling my hair out trying to find a solution for this problem-
When driving down the road, usually at speeds greater than 55 mph and usually in hotter weather, the vehicle will just shut off. Temp gauge stays firmly in the normal range, coolant level is fine. The vehicle will eventually restart after 5-20 minutes before repeating it’s little ‘siesta mode’.(It turns over, just won’t start) I’ve been all over the internet and can find dozens upon dozens of identical problems in 1998-2002 Bravada, BUT NEVER A SOLUTION! There are suggestions from wiring shorts to fuel pump to temperature sensor to PCM - but nobody has the courtesy to get back online and post if they ever found what the actual problem was. I can only surmise that either people just don’t feel like posting the solution, or they are still trying to figure it out (which doesn’t bode well for me). Anyone have an answer to this mystery?
My guess is a bad sensor. Crank or cam position sensor. Your problem is caused by heat. Those sensors can fail when heated enough, causing the engine to shut off, then after it cools, its magically fine.
By the way, post up your engine and mileage for the other guys who might have a better/alternative suggestion.
I am in agreement with Fender that it is likely to be a bad crankshaft position sensor.