Autoconnect to Car Media

My phone is bluetooth connected to my vehicle. I play Astiga through my car's media capabilities. Problem is that after I stop playing music and exit the app it reconnects and starts playing again the next time I enter the car. Yes, the car has been turned off between uses. If I disconnect my phone, I then lose my phone capabilities in the car. What do I need to do to prevent reconnection to the car until I initiate it.