Car had just returned from mechanic after getting new alternator, AC clutch, and various belts/valves replaced. Car drove great for about 20 minutes at 70mph, I slowed, and started accelerating again and the car began to hesitate/skip around 20mp to the point that I pulled over and then the car shook a few times and then powered down completely. Gave it a minute and then started it again and it drove great to 60mph and then started to lose it again and slowly dropped to 50mph and started to shudder again, pulled over, shook again, and then powered down completely. Car would not restart, it would turn over, but not catch. Prior to going to the mechanic, car was doing fine in terms of actual driving, never shut down or anything, my brake and battery lights would just flash intermittently and thus alerted us to an alternator issue. The catalytic (?) converter replaced in the last maybe four years, but my mechanic suggested that as a possibility though he can't look at it for a few days.
My car has 165000 miles.
My car has an automatic transmission.
I would suggest having the alternator checked to determine if it is receiving the proper amount of voltage from something called the voltage regulator. The voltage regulator regulates the charging voltage that the alternator produces, keeping it between 13.5 and 14.5 volts to protect the electrical components throughout the vehicle. The voltage regulator controls the field current applied to the spinning rotor inside the alternator. When there is no current applied to the field, there is no voltage produced from the alternator. When voltage drops below 13.5 volts, the regulator will apply current to the field and the alternator will start charging. When the voltage exceeds 14.5 volts, the regulator will stop supplying voltage to the field and the alternator will stop charging. This is how voltage output from the alternator is regulated. When the voltage regulator is not working properly, this may cause the alternator to allow the power the alternator supplies to drop resulting in the battery dying again. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.
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