My car had a check engine light on which the dealership COULD NOT FIX after having my car for a week. They first told me that my EGR valve had to be changed to a GM part. The new GM part didn't fix the issue so they refitted my original EGR valve. They contacted GM and they said I had to have a complete GM exhaust system ($1,600) since my car had an after-market cat fitted. When I asked will this definitely fix the check engine light they replied that it may not. I finally collected my car and took it to Stamps Auto in Queen Creek. Stamps Auto Queen Creek not only found the problem with a smoke check, fixed it and told me to take my car to do its Emission Test. I did as they suggested and my car passed its emissions check first time. I highly recommend the Queen Creek facility; they go above and beyond for their customers.