Electronics Sutting Off Intermittently While Driving or Parked

[jsmcbride1004]

Just bought a 2006 Mercury Montego Premier and as I was driving home, with the ac and the radio going, all the electronics started shutting down intermittently. The car didnt die and everything cut back on immediately after. I called the seller and he said he had the car derailed yesterday and that they cleaned the engine and to give it a day or so and it should stop, and that he had never had this issue. Could the engine cleaning cause this or is this the sign of a more serious issue?

Thanks!