I just got my car back from the shop, and I've noticed a couple little things. First, the car "clunks" when the heat is running. It'll clunk once, then there's a second or two delay, then another clunk. I noticed that it looks like the condenser spins up, because the revs increase during the longer delays. I didn't notice this before the accident. Do you guys know what this could be, or how to fix it?