Goofy Voltage

[Cardboardcat15]

Hi all, I have a question about my voltage maybe some of you can help me with.

O.k., so this really isn't much of a problem more than it is a "wtf is going" question. So anyways, I did the Big 3 about a month ago. Awesome, Got the cables I needed, I'm one step closer to higher voltage. I am getting pretty thrown off about my voltage fluxuation, however.

I have a stock 60 Amp alt and a Optima Red Top before and after big three. No changes.

Before the big three I had my volt meter hooked up AT MY AMP, got about a 14.2 readout starting my car in the morning which is normal, Alt isn't running hot so I get a higher voltage. Once I drive down the street, voltage drops to about 13.7 and stays around 13.7-13.8, and when bumping while driving fell close to about 12.2. When I had my Air Conditioner on my voltage would spike UP .2 volts, and when I had my blinker on it would do the same, only in unison with the blinker. Voltage would fall below 12v if I were bumping while in idle in drive. lowest was probably 11.0 volts flat. (at a stop sign or something)

Now after the big 3, Volt meter still at my amp, on a cool morning i'll start my car and get about a 14.7-14.8 readout out in PARK. When I shift into reverse, my voltage will spike up to 15.2. wtf? I assume it's due to less current draw from the larger tail light bulbs not being used and only having my single reverse bulbs drawing current? I am not really sure about that but I can understand it. While I am driving, my voltage will drop to 14.6 while car is still cool, and after driving for a few minutes it'll fall to about 14.0-14.1. And again, when I have my blinker and/or AC on, my voltage goes up. Lowest i've seen my voltage fall while idling in drive is about 11.5.

In a nutshell,

Why does my voltage go up with my AC/blinkers on, and why do I get 15+ volts in reverse and not in drive? =(

Thanks for any help!

[justinadams]

hmm. interesting. doesn't sound like a bad thing.

[MECHMAN]

Let me guess, is your vehicle a Honda?

(make, model, year and engine is always helpful when asking for troubleshooting advice)

[Cardboardcat15]

Let me guess, is your vehicle a Honda?

(make, model, year and engine is always helpful when asking for troubleshooting advice)

Haha not a Honda, but pretty damn close.

It's a 1992 Toyota Corolla DX 1.6L 4AFE

I need a new alt sometime soon, It's one of the things on my checklist =p

[JBERK]

Maybe it hasn't something to do with the alt spinning a little more when in reverse, the little bit of an rpm boost usually when it shifts gears?

[Cardboardcat15]

Maybe it hasn't something to do with the alt spinning a little more when in reverse, the little bit of an rpm boost usually when it shifts gears?

Ah, this might be true, I didn't know there was an RPM rise when shifting gears. I don't know much about cars aside from the stereo aspect =p

[bobmcbob_345]

Sounds like physics. Don't forget resistance increases with tempeture

[MECHMAN]

What you are experiencing is normal. The momentary increase in voltage is from the RPM flare that you get when it goes from drive to Neutral.

[Cardboardcat15]

What you are experiencing is normal. The momentary increase in voltage is from the RPM flare that you get when it goes from drive to Neutral.

Ah, O.k., thanks for clearing everything up, I thought it was weird that my voltage would go up the more things I turned on. Thanks everyone.

[JMZNeal]

i have a similar phenomenon. sometimes mine sits at 14.2-14.3 til i cut my radio on then it will spike to 14.4-14.5 til the music starts. Same thing with headlights. ? it might have something to do with the overall amount of juice going through the entire elec system but idk?