Well i went to my gf's house and forgot to bring some chips so i was gonna go to the store and get some. I get part way down the block and then all of sudden my car sounds like ****. I sounds like there is a hole in the muffler, but it cant be since its SS piping and i havent had it long. I also never hit the underneath on anything. It looks like white smoke come out my exhaust, but its hard to tell since its cold out and dark. The car kinda sounds like a lawnmower when you give it some gas and shakes alittle and the muffler goes putt putt putt. Any ideas for what it could be or what to look for?

 

Headgasket or loss of spark in one or more cylinders, although with the white smoke your culprit is almost certainly some coolant-related issue.