Misfires are most often ignition related. The spark plugs will talk to you if you don't have a computer reader. The wet plug with lots of carbon will generally be responsible. A reader will most often show which cylinder is missing. The four is easier since the plugs are easy to get at. Pull them on a cold engine. Rather than do the intake manifold work on the six a reader would be your best bet. I can't imagine how a rocker are cover could be involved.

Bill,

If you get time to look at a post I made I would be appreciative.
http://www.ford-trucks.com/forums/10...ml#post9556702

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