Porsche Enthusiasts Club Forum

I have noticed the voltage jumping up and down of late on my car. I have checked across the battery in case it was a gauge issue but readings are the same.

When I start her up the voltage sits about 13.2V. When I start to drive or put things on it often drops below 13v. Sometimes it even drops as low as 12.1V with nothing electric switched on. If I stop and switch off then start up again it returns to 13.2V.

The voltage can sometimes dip to around 12V by simply putting the lights on or something but not always. It also sometimes goes back up to 13V whilst driving for no apparent reason?

I have had no electrical issues, car starts 100% every time with strong turnover from battery, just feel this isn't normal behaviour.

First thoughts were maybe voltage regulator or the battery itself or dare I say it the alternator!

Over to the experts..........

PS Can you change a voltage regulator on a 944 alternator or is it a sealed unit?

Thanks

Stuart

The regulator will probably be a bog stock diode pack. There could be problems with a poor connecton to one of the cells in the battery as well. You will get a volts drop when there is a load put on the alternator when you switch the lights on as your are looking for at least a couple of hundrew watts from the system, 15 to 20 amps.
Al Cowan

I'm sure someone has said this, perhaps on another forum but yes you can change the voltage regulator separately.