alternator/battery problems

[RagingPanda]

I have a brand new alternator and battery from autozone. While the car is running they checked for me and it won't get pass 12.29. I thought the alternator is bad so I took it out and got tested at autozone and it passed all the tests. I don't know what's the problem is. All the connectors are nice n clean. So now my battery is dead and autozone won't let me get a new alternator because it passed all the tests. 1978 280z

[evildky]

voltage regulator, it's external on all S30's it's located on the inner fender near the alternator, it's square held in with 2 bolts and has one plug with 6 or 8 pins coming out of it, replace it, most likely that is your problem, the bonehead likely didn't realize when testing ont he car that the voltage regulator was a seperate part and said it was a nad alt because he thought it was a part of the alt as it is on all modern cars

[RagingPanda]

But I check the alternator and it has internal voltage regulator. The problem is gone now. It was a bad alternator and bad cell in the battery so it works fine now. But I don't know why my voltage meter isn't working anymore along with the cd player. The new alternator has a little copper cylinder that runs from the left to the right on the back. I asked them and they said it's a universal part that reduces noise. So should I take it out or just put it there?

[evildky]

that thing si a noise supressor, not a big deal, the stock alt should have had an external voltage regulator? check for an external voltage regulator in the inner finder forward of the strut tower, if it's fried it will casue the problems you describe