GMC Repair: electrical problems, dash lights, electrical problems

Question
All the dash lights are coming on sporadically and I noticed when the lights come on, the battery guage is going in the red, kind of fluttering back and forth. I also experience a slight loss of power when accelerating, but only when the lights come on. I had the alternator and battery replaced, everything was fine for a few weeks and it started again. I took the car back to my mechanic and both battery and alternator were again replaced but it has started doing it again. Yesterday it stalled on me while travelling 50 mph on a main roadafter the dash lights came on. It doesn't happen all the time, sometimes I can drive it for a few weeks without any problems. I don't drive the car alot...it only has 43K miles on it. My mechanic has suggested I take it elswhere,but I don't want to waste any more money than I have already on expensive diagnostics...every time I have a diagnostic performed (3 to date) it comes up *bad battery*...can you help?

Answer
Since there are approx hundreds of MAKES, MODELS and YEARS of vehicles out there, I can ONLY assume that you have something between a MOPED and a tractor trailer.

Please THINK before you ask a question as I am NOY psychic to know what you are driving.


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