Alternator whine
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Leave the amp ground at the battery. It's better than the frame or anywhere else on the car.
Is the new alternator an aftermarket high output alternator? Typically those higher output SI alternators are known for low output at idle. Their new guts that make them put out more power also mean they put out less power at idle...sometimes even less than stock.
I might also suggest you remove the alternator and take it to a shop that specializes in repairing starters and alternators. They will be able to test it. If you don't have a shop like that take it to a chain parts store as they can usually test them for you too. Make sure it's someone you trust knows how to properly operate the machine.
Thread Starter
Race Director
Joined: Dec 2007
Posts: 14,345
Likes: 4
From: Hartselle AL
St. Jude Donor '09
Leave the amp ground at the battery. It's better than the frame or anywhere else on the car.
Is the new alternator an aftermarket high output alternator? Typically those higher output SI alternators are known for low output at idle. Their new guts that make them put out more power also mean they put out less power at idle...sometimes even less than stock.
I might also suggest you remove the alternator and take it to a shop that specializes in repairing starters and alternators. They will be able to test it. If you don't have a shop like that take it to a chain parts store as they can usually test them for you too. Make sure it's someone you trust knows how to properly operate the machine.
Is the new alternator an aftermarket high output alternator? Typically those higher output SI alternators are known for low output at idle. Their new guts that make them put out more power also mean they put out less power at idle...sometimes even less than stock.
I might also suggest you remove the alternator and take it to a shop that specializes in repairing starters and alternators. They will be able to test it. If you don't have a shop like that take it to a chain parts store as they can usually test them for you too. Make sure it's someone you trust knows how to properly operate the machine.
Thread Starter
Race Director
Joined: Dec 2007
Posts: 14,345
Likes: 4
From: Hartselle AL
St. Jude Donor '09
Just wanted to close the loop here. It was as simple as a bad ground/neg battery connection. The aftermarket battery terminal connector with the piggy back bolt for accessory connections was not tightening correctly/fully to the battery. Replaced it with an improved connector style and all is back as before. No whine, good charging. Sometimes the simplest solutions are just too obvious.
Thanks for all the help.
Thanks for all the help.
