arrows

Hi all,
So this is an update on my starting issues from my previous thread, but it's a new topic so I figured I would start a new thread.

Battery: I had suspicions of a parasitic drain because I've gone through two new(ish) batteries in the past and have done some testing with a multimeter and can see a fast drastic drain when the car is off. I even unhooked the battery cables and the battery went from 12v to nothing. I saw it drain unhooked right before my eyes, so I figured it has to be a bad cell.

So I replaced the battery with a new one, and because of my possible parasitic draw, I decided to replace the voltage regulator with a new one, and replace the alternator with a new one as well. I did some parasitic drain tests before all this, but I couldn't find the fuse that was pulling power, so I decided to just replace these three things and start from there. It's not easy with one person and the fuse box under the dash.

Alternator: My old one was pushing out 14.6v on the battery when the car is running, so I thought maybe it was overcharging and causing the bad battery. That's why I decided to replace it. Now the new one is only pushing out 12.4 on the battery when the car is running. When the car is off the battery reads 12.8v. When I turn the car on with no extra accessories other than the radio, it goes down to 12.4. If I press down on the gas and raise the RPM's, the voltage on the battery goes up to about 13.3 - 13.4. From what I've read online this tells me that my alternator is working(?), however, why am I getting such low ratings when not pressing the gas? Shouldn't I at least be getting 13 - 14v when I start the car? I tested the grounds on everything and it checks out fine. I even made sure that I had the fields hooked up properly on the new alternator. I went from a single field alternator to a double field, but read the instructions to ground the top field, and use the second field to connect to the voltage regulator. I tested the battery post on the alternator as well with a multimeter and I can see 12.8v when the car is off. The post reading goes down the about 12.0v when the car is on.

I've been watching so many videos and reading so many threads on alternator issues, parasitic drains, bad cell battery, that my head is spinning. Hoping someone can point me in the right direction. I'm hoping that my alternator is not bad, because it just arrived two days ago.

I've also read that getting around 12.5 when the car is on, and the voltage going higher when the RPM's go higher, is normal for newer vehicles because of the voltage regulation on the battery. But since this isn't a newer car, I figured that can't apply here, right?

I left my battery hooked up for about 30 minutes and the battery went from 12.8 to 12.76. I don't know if that means I still have a parasitic drain, or if that's normal discharge within 30 minutes.

Thank you for any help!

xaza

You will drive yourself crazy replacing parts without knowing if there is anything wrong. To try and find parasitic drain you will need to check for amp draw off battery. This guy has a pretty good video for this process.

arrows

This is a great video. Thanks for sharing. I'll test this out again tomorrow and share the results.

arrows

I ran the parasitic drain test, and everything looks good. No amps and no mA. When I was first doing some parasitic drain tests, I noticed that my glove box wasn't closing properly because of the latch on the inside of the glove box being too forward. I pushed it back and the glove box closes completely now. I can't say for sure that was it, but if anything that might have been the cause.

Now I'm just wondering about my new alternator and it not pushing 13 - 14v when the car is started. Only pushing 13.4v when I ramp up the RPM's. Any thoughts? Should I return this new alternator and install my old one? My old one was pushing 14.6v when the car was started, and I'm worried that was over charging the battery.

I took the car for a quick drive and it was great. No throttling issues, no idle issues. It was smooth. Can't wait to get the electrical issues behind me so I can work on the suspension next.

xaza

I am not as familiar with the older cars like some of the other guys here but 14.6v sounds totally fine to me. I agree that 13.4v is a little low, especially if you are revving it, but should be able to charge battery back to 12v. I would run it as is for now and see if you end up with a dead battery again. If not then you have a spare part on the shelf if/when it does go out.