In the knowledge thread I posted a link about the voltage regulators and where to find them. I have been doing research because my alternator is on it's way out. It is mostly at 13 VDC and often drops to 12 VDC when my AC compressor kicks in.

Their are multiple sources and manufacturers for these regulators. The ones for the 996TT is used on about 20 different cars too. Some guys have had issues getting Wood Auto to do online orders if you are in the US. Here is some part number compatibility information if you are looking to tackle this yourself.

Bosch regulator
Bosch interchange part number: F00M-145-350 (which supercedes PNs: F-00M-145-200, F-00M-145-209 and F-00M-145-225)
Porsche part number: 000-043-206-37-M14
Bosch catalog with information: http://www.bosch.co.nz/content/langu...pare_Parts.pdf
Wood Auto replacement: VRG46444
IAT makes some other interchanges as well. Here is a link with that info:
http://www.iat-usa.com/Regulators.pdf

The replacement of the regulator is quite easy. If the regulator is the only issue and the bearings are okay, you can save yourself a pretty penny just swapping this out. The bearings are sealed and ususlly outlast the regulators.

See post #2 here for the links to the DIY and etc...: https://www.6speedonline.com/forums/...-post-one.html

 

Mine seems to be failing at this time.
I have not had the alternator out of this car. Is the VR attached to the alternator or is it installed elsewhere?
scott

 

It is attached to the alternator. If you look at the DIY procedure in the knowledge thread I linked above it will show the location in the voltage regulator replacment procedure.

 

I replaced my VR and it reads roughly 13.8V on start up. When the car gets warm and I turn the AC on it can drop just below 13V. Does anyone know if these are normal voltage readings?

 

Yeah ... im in the same boat ... I replaced the alternator AND voltage regulator .. starts up on 13 and goes down ...

 

a tired battery can cause similar symptoms.

 

It has a new battery.

 

Can anybody confirm the Bosh part number for the complete alternator on a manual car. The OEM part numbers are 997 603 012 05 which has been replaced with 997 603 012 07.

Thanks.

 

recommend rebuilding the alternator since it has to come out to replace the voltage regulator. i had same issue, that's what i did.

 

Hey, i'm about to replace my voltage regulator, and i was wondering if replacing yours fixed it.
I dug up this thread after seeing your (i think) video on youtube, and your symptoms match exactly what i'm seeing on my 02 tip turbo.

 

I had exactly the same problem on my car last week. The voltage was dropping a bit below 12 volts with the a/c selected. Decided to replace the regulator only and now I got a nice 14 volts and a bit over 13 volts with the a/c selected. Less than 2 hours job and only $40.00 for a Bosch regulator!

 

nice peice of information.. thanks for sharing

 

I put in a new alternator a year ago and it reads the same as the old one - I don't think I've ever seen 13 unless I put the car on the charger for the night. Did I get a bum replacement too?

 

Slider, did you change the whole alternator, or just the voltage regulator?
I get up to 13.3V if i turn everything off and the car is cold.
After the car warms up and with the AC on, i'm getting like 12.2, which slowly drains the battery (or just doesn't charge it enough), and i can't start the car back up after stopping.

 

Yes, I replaced everything - just to make sure. I plug in once a week now just to make sure the battery stays completely charged. I know the alternator is not topping up the battery to its capacity.