The general consensus is, if it's rattling a lot, you should bring it in to have it looked at. It's possible that it's just one of the guides, and you'll be in and out in a flash, but the KA is an interferance engine, meaning that if the chain goes, so does your valvetrain. It's worth it to have it looked at, and possibly save yourself the cost of a new engine (unless you want to swap <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt='

'>)