What's the best way to find a dead cylinder?

four pages and a week later... we've got pics of the plugs, at least a dozen suggestions to check the compression and probably twice as many to ground out wires or squirt liquid on runners.

if you haven't popped the valve cover off yet to inspect for damage or something amiss, it's time for compression or a leak down test. you've already got the plugs out. if that comes up inconclusive, i'd back track to electrical: cap, rotor, wires, coil, ecu and then circle back to a vacuum leak.