Smithaero448

Was wondering if anyone had an idea of what could be going on or had the same problem the headlights and dome lights are pulsating only at idle i had alternater and battery tested and both are good.?

08'MustangDude

Pulsating is usually the alternator, one or two of the diodes are bad. Doesn't
matter that it tested good.

Smithaero448

Ok thanks man the new altenator doesnt even have 4 thousand miles on it yet you think it could be bad already?

08'MustangDude

It could be, and check all the grounds too...

Urambo Tauro

Yeah I once had (a reman) one go bad in <50 miles.

Smithaero448

Ok thanks ill let you guys know if the altenator fixes the problem.

Derf00

Absolutely can be bad. Where'd you get it from? Guy i work with has a Nissan Fronteir, chased his tail for a couple months trying to fix a similar issue. Replacing the alt was one of his first things he did.. Long story short, he finally took it to the dealer, bad alt. Replaced with another new alt or a remaned alt and problem solved. He originally had a Duralast brand alt that he bought.

Smithaero448

Just changed the alternator today no more fluttering lights cant believe that altenator was bad in 4000 miles thanks guys appreciate it.

Derf00

Glad to hear you fixed it. Hopefully exchanged for free under warranty?

Yuh, hard to believe only 4K miles on yours and my coworkers was bad out of the box! What brand was yours?

Gravydog316

loose wiring?