I own a 2006 Saturn Ion. My car is at 80,000 but since this started a few months ago I would say 74,000 miles was the occurrence. The car was running rougher and rougher. I knew the sound to be an exhaust leak. I had my mechanic look and he just checked the hoses, and saw nothing. I kept driving with it. I started getting bad headaches, and slightly nauseous when I drove long distances. I travel 400 miles roundtrip when I visit family out of town at least once a month. I also noticed the odor of exhaust in the cabin when I started my car. I cracked my windows when I drove and when I had a chance my mechanic found I had a cracked exhaust manifold. He said he has seen the same crack in the same place on the same GM engine 2.2L 4cyl about 6 times this year already. Chevy has it on cobalt I think. He said it is probably a factory defect since it is wearing thin in the same place. Considering my car was poisoning me for months I think this qualifies as a safety concern and should be investigated. I knew the sound and warning signs because of past experience. It is a danger to the majority of drivers, because they don't.

- Houston, TX, USA