Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
It sounds as though you are loosing electrical from the alternator/battery. If you have a voltmeter or 12 volt test light once the engine begins to falter, check for voltage along the circuit that is failing and I would start with the voltage to the main fuse box that houses the fuses for the fuel pump and the ignition. Something is probably loose.
The only other thing I can think of for right now is a security issue. Does this have a security system and if so is there any security lights on or flashing at any time?
Yes you did.
Try a new ignition switch.
I take that back. I would try retrieving all the codes first, from all of the modules, which includes the body control module to see if anything is stored that may give a clue as to what is going on because it may just be a faulty body control module.
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