After I drive for more than 15 minutes when I turn the engine off I get this huge blow out the back of my car (this huge bang sound). I have talked to a few people and they say it is not only out hte back but the air blows out through the carburator. But they haven't the slightest clue what is the cause. ANy help on why and how to fix it would be great. I have also heard if you dont fix it, it can light your engine on fire so I was just looking for some insightful knowledge.
Appreciate the help

 

I was thinking it could be due to the carburator letting in too rich air. And if i tightenend the screw it might help. any help would be appreciated I still havent fixed it

 

Carb sounds definately in need of a tune up.But worn valves can do this as well.

Start with a tune up on the carb try tuning it out and make sure that its not in need of a rebuild.And carbs do need attention theyre not like EFI which can be good and bad depending on you and your knowledge.

 

your problem is after you turn the car off raw fuel in burning in the exhaust system due to an over rich condition.....try this have the car in gear and shut the engine off I bet it quits