dimming lights
 

when i am at idle my lights dim in my panel and my volts go down they use to go back up but now it only sometimes goes up is this my alternator or my battery i dont know how old easch one are

could be alternator, or voltage regulator. Autozone checks them for free.

my car does same thing...alternator is fine brand new bat..chaning regulator this afternoon...will let ya know if it fixes it

Did the regulator fix it?

Rick

Sounds like a stock alternator on an engine with underdrive pullies to me.

Take care,
~Chris

Mine usually does that if it idles below 800 rpm. After that it goes back up and stays up while im driving. I have a brand new alternator too. I think the 75 amp stockers arent that strong. i wanted to do a 130 but didnt have the time cause i needed my car to run. :(

Do you have a good ground from the block to the chassis? I changed battery cables, when i had my '84 and the lights would dim at low rpm. I added a ground cable from the block to the chassis and everything worked great again. Just something to consider.
Most likely though it's a weak alternator/regulator.

My mustang just started doing this as well. But its not just at idle, its any time. I was thinking its just a bad conection or ground, but havn't had the time to look for it.

Waiting for your answer...