Mass911

Just last night after leaving a store I fired up my 89 3.2 targa carrera and the alternator light remained illuminated. Running the engine up to approx. 2300 rpm caused the light to go out.

When testing the battery shows no charge, while the lighht is on. After running up the rpm's the batt shows a normal charge (13.5v).

anybody have a guess as to whats going south??

Trak Ratt

The sparkies can give you the tech terminology but simply put, I think your built in transistorized regulator is caput. I understand that there are several circuits that control the output at different speeds. Your low speed one is bad, at higher speeds it switches over to a different circuit. You may be able to get it rebuilt but time wise it’s easier to just get a replacement. Don’t low-ball the replacement I heard to many horror stories about how long they last.

Burnell

On an 87 Carrera you can purchase the voltage regulator separately from the alternator. The dealer has them and maybe aftermarket people.