I've got a 2004 E-150 with the 4.6 engine. I've got some misfire happening but don't know where it is. I've replaced all the plugs as it was time and I replaced the Crankshaft sensor and there are no codes now. I replaced the No 7 COP but still have a misfire somewhere. How do I test these coils to see which one it is? I read that you can buy after market COP's on e-bay for under $100 a whole and I wish I'd have known that before. Does anybody know the company that has them or would it just be better to find this one COP that's giving me trouble? I drive the van for a living doing deliveries and it has to last me a long time! I only drive Fords and they always last my over 400,000 miles so the more I know the better.

 

You can move the new coil and see if the misfire gets cured as you swap cops. I think you can also perform a compression test. Jbrew did a writeup on how to do it I believe

 

If you are getting a misfire, are you getting a flashing CEL or is it set ?

You should have a DTC set that is a P030n, where n=cylinder number.
P0300 is a random misfire ( think that is it ).

 

I bought one new one and in the process of swapping it out with the others. I just found a whole set on e-bay for $63! Can't believe that price! I'm gonna swap it around but as cheap as they are I'll probably just buy the whole set and be done with it. It's not showing any codes now. It was the crankshaft sensor but I replaced it and it went away but the misfire is still there. The Haynes book doesn't show any way to test these COP's but I know there has to be a way.