when i turn on the heater I will get heat, but only for a little while, then the air cools down & never gets warm again... I am used to other cars (also w/ auto climate control) that will remain warm/hot and I have to end up turning them down... i end up turning the 996's heat up untill its at the max & then it still looses its heat.... is something wrong?

 

Two guesses
1. It's too warm outside for the climate control to allow the heat to run full force. Turn the system on manual and see what it does.
2. You need to flush your coolant, check the thermostat and complete radiator system. That is where the heater draws its heat from.

 

When I lower my top and turn on the heater sometime I have to raise the temp. because it's too hot in the cabin even with the top down. And the blower is strong considering this a Porsche.

Over the winter, there were early morning fun runs with temp. in the 40's and I had the top down and cruised at 130-150 mph and still feel comfortable inside the cabin.

Maybe your internal heater plumbing is clogged, leaked. The heater system draw heat from radiator coolant syst.

 

could be something electrical like a bad temp sensor in the climate control system. had a similar issue on my 330i bmw, changed the control unit and it was good to go.

 

another possibility is bad mixture of coolant... to much concentration of coolant will not heat up per designed.

 

Flush your coolant or check heater core for bad circulation.