Electrical problems...
 

Well, now I've got another issue with the car. The charging system doesn't appear to be working correctly. When I turn on my headlights, the voltage drops way down and tries to stall out the car, even when I'm accelerating. While driving, the voltometer jumps between 14 volts and 15 volts and won't stay constant. If I have the car idling and turn on the headlights, the car stalls out and goes completely dead with no power at all. I can jump the car and get it running again, but as soon as I shut the car off, it loses all power again. I have a feeling the battery may be sulfated and that it's just not holding a charge. If the alternator was going bad, it wouldn't be putting out the correct voltage, which it seems to be. Any ideas?

there might be a short underneath your tansmission on the starter or on top near the battery. find any wire that has its skin melted off that could be touching the ground chassis. Im pretty sure its a short, thats what my problem was. Eitehr that or the main fuse box, the black wires that bolts on to the black middle fuse could be loose so the alternator is not charging and its running on the battery itself. Make sure the wires are not loose

sounds like a bad battery. if u had a melted wire trust me you would notice more than just power promblems. like lets say a short on your starter will cause the starter not to work on top of draining the battery. go to autozone or advanced and get a battery check. quick simple free. oh oh oh also check to see if there is water in the battery. also winters tend to kill batterys

Yea, I didn't figure all of a sudden I'd just have a bad connection. I've recently removed and installed the starter, so I doubt a bad connection there is the problem and I've looked at all my connections and they look fine. All my fuses are fine, I just checked them out today. I honestly am thinking it's the battery and that it's just not holding a charge and that the car is running off just what the alternator is putting out, which would explain the stalling out when I hit the brakes. I also think it's the battery because I ran it dead quite a few times this passed winter and a few times before that, not to mention the battery itself is at least 4 years old. I'm going to take the battery out of another car and give it a try and see if it works correctly then. If it doesn't, I'm pretty sure the alternator is going to be at fault.

Turns out that it was in fact the battery. I took it out and put the battery from my girlfriend's Mustang in the RX-7 and it worked perfectly. Just to make sure it was the battery I put the bad battery back into her car and started the car up. As soon as I turned on the headlights or any of the other electrical draws, the voltometer quickly dropped and would not charge back up to 14.5 volts until I turned everything back off. So it looks like I'll be buying a new battery for the RX-7 now.

you can pull batteries and take them to autozone and they will load test them for you. You also could have put a voltmeter on the battery and that would at least tell you if it is highly discharged (low voltage)

what should it read when you do that?

12.4v across the battery post is about 75% charged, anything below that needs charging.

what else could it be if the battery is good and the alternator is good too? im having the EXACT same problem

If you are ABSOLUTELY sure it's not the battery or alternator, then I'd check your grounds and connectors and be sure they are good. Usually, it's the battery that's at fault first, then the alternator, then the wiring.

it did turn out to be the alt. i made the guy at autozone try it 4 times (really pissed him off, and i always knew those machines were pos') then got the load test done (since they finally got a new one after their old one broke) stupid fuckers, i hate this town especially since im the ONLY FC in this town! Ricers love this car btw. Looks like im dropin $100 for a new alt :(