Is this one to aviod?

[peterzs]

Sounds like the inlet plenum

http://www.pistonheads.com/gassing/topic.asp?t=921250

reckon he will take £650 cash, with the belts done and all the new bits might be worth a look, now the rattles can go on for a bit before it needs doing. Always ebay for another one and take a gamble.

EDIT Or the purge valve as Pete says. :-)