I got out of work today and noticed my car was backfiring alot more and wayy louder all i have is intake and exhaust. My car usually backfires periodically and not too loud. But today it sounded like an srt-4 so i got home took a look at da engine bay and exhaust for soemthing unusual but didn't see anything then i turned my car back on and it was back to normal. Any ideas why this might happen?