Unfortunately I have to take my Xfire to the shop in the morning. Yesterday on my to work I got on the highway and when i let off the gas there was a loud clicking noise coming from the rear of the car. I can't fell any clicks but I sure do hear it. It only happens when I let off the gas. Nothing when I step on the gas. Faster I am going the faster the clicks. They will also continue the hunt for whatever keeps tripping the check engine light. It's been an on going problem since I got the Car. The dealership in Hawaii never found the problem. Now that I have Moved to Fort Benning Ga hopefully they can find something. Wish me luck and I'll post once the dealer let's me know whats up.