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!!! I have been on the phone with the customer complaint department daily and the district specialist, April, but to no avail. I am not allowed to speak to anyone higher than April. Everyday is a new story and still I am out of a car for the last 60+ days. This is truly ridiculious. A large American company like GM obviously does not value its customers. The complaint department is designed not to let you speak with anyone of authority. The upper eschleon of GM has insulated itself so that no one has to be bothered by the unsatisfied customer with a legitimate gripe. Beware of the GM "certified" cars !!!