93 Buick LeSabre randomly dies - all electrical is gone

Grounds and battery connections, first then power to the ugn switch nunmer

1. Do you mean headlites or dash lites, if headlites got to be a bad main

have a shop the crank position sensor (sometimes called cam sensor) when these go bad they cause similar symptoms, actually they cause all kinds of weird things to happen. also check to see if the ground strap from the engine to either a fender or firewall has not rotted off.

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Even the headlights go off. We cannot find a ground cable at all from engine to chassis.Where should I look on a front wheel drive GM to find it?

Could the cam sensor cause the whole car to go dead, even down to the headlights?

No

The next time this happens flex the battery cables along their entire length then retry. Cables can develop corrosion internally, under the insulation, causing the vehicle to exhibit the symptoms you describe. Look for any "swelled up" areas along the cables. As others have noted, check all connections and all grounds.

Check your cables from the alternator and check the main engine block grounds, after you have checked everything a couple times and if you can't find the problem take a look at the sensors, I had the exact same issues on a non-gm vehicle, the dealer checked the wiring for bad connections, check all major items (battery, cables, fuel pump etc.) and found nothing. It was suggested that they change a crank position sensor and that was the fix. So to answer your question, yes a sensor could cause this problem, but FIRST check the wiring a couple times and if possible plug a code reader into the car, see if there are any codes. If you use a good reader it will be able to give real-time events while your driving. A passenger can look at this next time the car dies.

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