Yesterday I was driving my 94 automatic v6 camaro and went into the store real fast and came out and started it. When I did, I heard a loud boom under the hood and my cars rpms shot up to about 3500. I put it in reverse and tried to drive it but it seemed terrible on my brakes. Any suggestions on what it could be?

 

Start by checking for damaged vacuum lines & vacuum leaks, or anything that looked different before the car went boom.

 

How loud of a boom? Did you feel the boom too or just hear it?