Buzzing voltage regulator

[nailr65]

Anyone have any ideas how to correct this issue? 
 
I have been having problems with a buzzing voltage regulator on my Gran Sport.  What I believe to be the original started buzzing, so I replaced it with one from a local auto parts store.  The new one was like an empty tin can.  This solved the buzzing but it made the voltage dash light come on.  This was irritating so i started a search on ebay for something nos.  Holy expensive?  Found another at the local auto parts store which was a bit heavier and cost about $45.  I fired it up, no light, no buzzing.  GREAT!  Nope after the car gets warm and I shut it off, then fire it up again, the buzzing returns and the dash light flickers in sequence with the buzzing sound.  HELP!!!!

[Brian]

Its your battery.  It is about to die on you.  Put a new battery in the car and the problem will go away.  Most likely has an intermittent open circuit in it and is causing the volatage regulator to chase a moving target, and therefore buzz.  Had it happen before and did all the stuff you did with the same results.  Put in a good battery and the problem went away. 

[nailr65]

Thank you for the reply Brian.  I have a new battery.  Could it be a loose connection somewhere?  I have been chasing this for a while.  Only happens when the car is hot an then shut down and fired back up.

[Brian]

If you do not have a good ground to the body, that can cause it as well since the voltage regulator grounds to the firewall.  Do you have the small ground wire from the negative battery cable connect to the inner fender like it came from the factory?  If so, the next place I would look is the alternator.  If there is a diode in it that is breaking down when it gets hot, you can get odd things happening like this.