I purchased the pro theme and its not working

These forums do not support commercial products. Only the free plugins downloaded from http://wordpress.org/plugins/. Please contact the plugin’s vendor directly with any questions about commercial products.

Sorry to hear that. FTP into your site (or whatever file management application your host provides) & rename the wp-content/plugins/car-demon/ folder. That should bring you site back up.

Then try to contact the developers directly.