1998 Honda Civic "clanking" noise :(

Hey all, first post.

I recently just came back to school at virginia tech and had to get my radiator replaced because the guys said it was "busted" and it had indeed leaked all its antifreeze out.

Anyway, a couple weeks later a muffler hanger broke and i went to a different place and ended up getting the whole exaust system replaced :O

So $700 later and a couple weeks after both these incidents when I drive to classes and only while im accelerating (on hills and on flat road), a metallic clanking noise occurs somewhere in the front of my car (almost sounds like the outside of the front, but I cant tell).

It is very noticeable with the windows down and even when they are up and the music if off. It almost sounds like a clock when im accelerating at all, "clank.. clank.. clank.. clank", if i drive for more than say 10 minutes it will shutup but it varies from soft clank to loud clank.

The weird part is, when i shut off my car after coming back from class or something (only like a 5 minute drive) it will periodically (every 30 seconds or so) make the 'clank' several more times even though the car isnt on or anything.

I went back to the exaust people once and they put a shield around part of the exaust, thinking it was a vibration, but i told them it wasnt, but hey, they failed that time, im gonna take it back soon. It is a distinct clank, like hitting the metal part of a wrench to a screw driver.


Any thoughts would be extremelly helpful! im no mechanic!
What in a car would be a part that still moved causing a clank after the car is turned off? (and I don't think the radiator fan has stayed on or at least I don't hear it).

Thanks in advance!