I looking for a mod to change the settings so all the planes start cold and dark in free flight. I like to start the planes myself.

Create a new flight at your favorite airport where you live.  Set it up at a proper parking spot, turn off
the engine if it's running, turn off all electrical power, set the parking brake and make sure all 
controls are set to where they should be....Mixture to full rich if it's a prop aircraft. Now "Save as Default
Flight".  That should be an option when saving a flight.  

From then on, no matter where you chose to start your flight and whatever aircraft you choose, you
will be "cold and dark".