I am new here, first post and i will create a introduction later. Last week i bought a fairly cheap 996 with aero package, but it has some issues to sort out.
needs new brakes, oils pressure sensor, fix some oil leaks and a refreshing of the interior.

But my main concern at this moment is the charging issue. when i start it in the morning i have a tps/abs and battery light on. i can see it is not charging as the gauge stays at 12v. when revving above 3000 rpm the gauge stays at 12v but the lights go on and off a few times. Then when i start driving the voltage goes to 14v and all lights go out.

It almost looks like the alternator needs to warm up.I am thinking about a bad alternator or maybe a bad ground or positive cable. I am a mechanic so i am not afraid to get my hands dirty and like to work on them, but i sometimes do need a push in the right direction.

 

Bad voltage regulator. It fails to excite the coils inside the generator and therefore you need the generator to rev higher than idle in order to get it to charge.