I have a check engine light, and Onstar indicates a code P0008. I recently had P0006, but the engine light would go off and on. I'm taking the car into the dealership on Thursday. I read that P0008 deals with the Cam Shaft and timing belt. What can I expect, my extended warranty is done, and I have 77,000 miles on my 2007 CTS? Is timing chain covered under 100k warranty? I'm kind of nervous about how much this is going to cost. Any insight is appreciated. Thanks.