A couple days ago, my car started running like it was kind of "missing". When i got it into my garage I had white smoke coming out of the exhaust and the garage filled up with a gasoline smell immediately. I checked under the car and I was dripping gasoline off of the underside of the exhaust towards the rear of the car, and I pulled a P0303 code (cylinder 3 misfire). Any ideas on what might be causing this?