voltage drop when let off on gas

[signalnc]

Just like the tittle says, when I let off the gas, say to make a turn or stop at a light, the voltage drops down to around 12 and then kicks right back up tp 14. I just replaced the battery. Quite honestly I don't know if this was happening before I replaced the battery or not, since I don't really drive it alot. It's my wife's daily driver. The alternator was replaced in August. I'm thinking of replacing the belt for starters. any ideas?

 

[bspurloc]

I would guess a bad alternator, but its new, then I would guess an old battery but its new.
Maybe check the battery connections for corrosion.
Does it due it with the ac totally off?

 

[Matt]

Check all your grounds in the engine bay. Also make sure your battery connections are tight using a spanner (wrench), not just your fingers.

I had an issue like that a while ago and it was the battery connections and grounds. Took the groungs off, sanded the grounds and connection points and tightened the battery connections...all good.

 

[swede]

Hook up an volt meter to B+ on the alternator and a good ground. Then you can see if it's the alternator or not. Just because it's new doesn't mean it's perfect. Could have a bad regulator inside

 

[marinegrunt]

Some good suggestions above. One thing I've noticed is people tend to overlook the battery terminals. Like mentioned, clean the battery terminals. I would also clean the terminals on the alternator. I once was replacing a tranny. There were like 3 grounds that hooked up to a stud on the tranny. It was late and I was almost finished. I told myself I should clean those grounds. Since I wanted to get it done that night I didn't. The car wouldn't start and the gauges and interior lights were going nuts. The grounds were fine before. Like mentioned above, clean all connections and also check the alternator. It could also be something else like engine performance causing the drop in voltage. Start simple and work your way up.

 

[signalnc]

thanks. I'll try what was suggested