[Greg J]

I own a 2008 C6 Corvette with slightly more than 53,000 miles. I love the car and it has been mostly problem free for the past 7 years. Three months ago the generator/alternator failed (it flatlined). I replaced the alternator and everything worked fine for about one month. Then suddenly the volt meter (on the dash) started to show the system over charging. The normal reading was 14.5 volts but it started to show 18 volts or more. I checked the battery with a meter and it was registering 19.89 votes. After having this happen three or four times I concluded the voltage regulator in the alternator was failing and I replace the alternator for a second time (FYI, I ran the engine for less than 30 seconds each time it was overcharging). I have just finished the repair. I turned the car on and everything worked fine (volt meter showing 14.5). After running the engine for several minutes I turned it off and restarted the car and the volt meter on the dash read at +/-18 volts. I turned the car on and off several more times and it jumped from 14.5 to 18 volts. Does anyone have an idea on what is wrong?