when i got my sunfire the guy said that the exhaust was knocking a bit, so what ever i only paid 300 for the car. so a week later i put the car up on some ramps and go under it to see, i found out that it was off of 2 support hangers so i tighten them up and thought it was all good.....drive it around the block to see if its fixed and NO the noise is still there. if any one has had this problem before please let me know what it is