Ray S

I believe I may have an alternator problem on my 996.

I ran a few errands in the 996 over the weekend and on the last stop to the supermarket I came out to a dead battery. The battery is almost new (only six months old) and my trip was fairly long so the alternator should have that thing fully charged.

Got a jump and the dashboard voltage gauge jumped up to 14 volts, but quickly dropped to under 12 on the drive home. I hooked up my battery charger overnight and went out again for a very short trip the next day. When I started the car I had about 14 volts on the meter, but this dropped to under 12 about 3 miles from home.

What does your voltage gauge read on your cars when you turn the key (prior to starting)? How about when you are driving down the road?

TIA

Barn996

14 while driving down the road, don't know about before starting.

chsu74

My volt meter shows 14V before starting and as it cranks it will drop. After it starts, the volt meter will go up to 14V and then down to 13V.

Mark I

Ray: Nearly certain charging issue. Many auto parts places will test for free. Be suspicious of internal voltage regulator, which can be replaced at a fraction of the cost of the entire alternator -new or reman. Sourcing the part can be difficult, but others on the forum have found them. GL

Ray S

Good to know, thanks for all the replies!

Ray S

Went to Autozone and had them check it out. I definately have a problem with the charging system (alt or internal voltage regulator). I was not getting any positive charge at all from the system and battery voltage was falling as the car was running.

How do I find out which?

Mark I

If you're considering DIY, check this link:
http://forums.pelicanparts.com/porsc...placement.html
The source of the problem has to be determined through testing; surely someone locally that can do that. Also lots of info on the web. GL!

nick49

If you have a multimeter check the battery voltage not running when it has been disconnected from a charging source for at least an hour. Then start the car and with it running for at least a couple of minutes and ilding check it again. Now with it revved up a bit say 2500+ Rpm check it again.

First check should be lowest and third highest, if everything is working in the charging system, if third is lowest the alternator/reg is bad. If second and third is higher than first, battery is bad.

This is a simple and rudimentry check that can give you ideas what to look at. GL