I started my car today started fine drove to the gas station to put air in a tire.... I then put my car in drive and it started to idle rough then stall i could not get it started again its cranking over like it wants to start and then it sound like it back firing i have no idea whats worng any ideas would be great thanks

 

Ignition timing is incorrect. If it idles bad, look for vacuum leaks in the hoses and clean your IAC valve. About engine backfire; check your spark plugs, plug wires and distributor cap/rotor. Maybe this will help.