Hey guys. Got a problem. My alternator makes a humming noise when the ignition is off
And runs the battery down. Also the choke light comes on and the relay under the hood buzzes. Was fine till hooked msd up. But even when I unplug each wire still hums. Alternator charging. Its an 87 camaro 327 motor not .original. Any help would be appreciated . Thanks.

 

you having a stiky relay somewhere...i had same problem....i hapen to be relay hanging down in the fender next to the batery...when i opend it it was all rusted

 

Yeah I noticed that one I actually unplugged it the light goes off but the humming still there

 

I'm having the same problem, only mine hums when the key is on. When I unhook the brown white wire it stops. When I start the car the alt squeals like a loose belt but it's not. And is not charging the battery. Also alt get really hot really quick. It's also the 4th alt I've put on since the problem began. Any ideas would b greatly appreciated