Driving thru town today I got an alarm.(dinging noise)Looked at the dash and it had a light on that said "check gauges". I looked at the volt gauge and it was reading about 10V. Took it to auto zone it read 11.68V. Iv'e had some weird electrical issues lately. Got it home and parked it. Several hours later I went out and started it and checked the voltage it read 13.68V. If an alternator is going bad will the voltage fluctuate? I pulled both battery cables off to see what would happen, it kept running. It was still showing 13V. The alternator is making a whirring noise at times. Other times it's quite. Iv'e ordered a new alternator form auto zone. Won't be here till Wednesday due to the holiday. What do you all think? Bad alternator?