arcane start it up, rev it up a bit, then let it just idle. get out, pop the hood, and remove #4 cylinder spark plug. if the cylinder has been lighting up, you will hear a noticable drop in the sound of the revs. if you do, good, plug it back in, and repeat with cylinder #3. if you've lost compression or your sparkplugs are dead, you wont hear a difference after you remove the wire.
hope this helps <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'> its the "ghetto compression test"