Like rkvons implies, a failed injector is a possibility. However, with sudden total misses, a cleaning job has little chances of success. If it fails enough at one time to roughen the idle, then disconnect injectors one at a time...the one that does not make a change is the culprit. Of course....hope it is one of the front three.....There has been at least one case on this forum where the driver transistor for one injector was the problem, not the injector itself. I think the transistor was a discrete component and could be changed .
EDIT: Yeah: found here :
http://www.automotiveforums.com/vbul...d.php?t=507692
HOwever, as simple things are best to begin with, tell of the result with the new spark plugs....mmm.if need a trick for the rear ones.....I can suggest....
http://www.automotiveforums.com/vbul...d.php?t=599442