Well, hmmm. I took the car up there today at the bright and early time of 7 am. Rode my bike to work. At noon, I was out off work and got a call that my car was ready. So I hauled my pretty green bike back up the hill to get the car. They said it was a loose heat shield and some missing clamps (not sure what those are). I didn't get out of the parking lot when the noise came back. They said, come back at 1:30 and he'll take a ride with you to see if he can hear it. So I did. At 3 he finally came out and said let's go for a ride. he explained to me that he heard "a" noise and fixed what cause that. Again, we didn't get past the end of the parking lot before he said "What the hell is that?" It sounds like chains dragging under the car, not super loud but loud enough and annoying. He has no idea what's causing it. it doesn't do it while it's up on the rack. And he didn't have time to get back to it today so I rode my pretty green bike home. That's where it is right now. Sigh.