I bought a "certified" pontiac GTO there was a problem with the engine my car has been at the dealership since January 7, 2011 and it is now March 12, 2011. I just bought the car in August 2010. The dealership took the engine apart and rebuilt it but the knock continues. If the car had not been under warrantee, GM would have told me to buy an engine and my car would have been fixed immediately. Because it is under warrantee, they do not want to change the motor instead they are holding my car hostage while they try to figure it out!!!... read full review »