I have a 2001 duratec that developed a #6 cyl misfire at idle.
It would misfire then clear and repeat about every 3 mins.
The car has 56k on it, so I replaced the plugs and wires, the plugs had opened up to .070. I figured I had this problem whipped.
Started it up same problem. I found that #6 fuel injector was not firing when the miss would start by listening to it with a long screwdriver. No big deal replaced the injector but no luck same problem. Well it must be the ECM or the wiring in between it and the injector. I unpluged the harness at the ECM and just barely caught the glimer of moisture across the plug end. Out came the old hair dryer to dry things up, this did the trick.
Like to drove me nuts. Maybe this will help someone else.

I have a 2000 Duratec as well, with 56k on it also. Weird, but i had the exact same thing happen about 2 months ago. Engine would misfire causing a "bucking" feeling which scared the hell outa me. Computer read that #6 was the one. After also seeing water on the plug i replaced it. 3 days later....same thing. After that i took out a heat gun and heated up the coil from #6, as the duratec's do not use the normal plug and wire, but instead coils. after heating it, i swithed #5 and #6 applying tape all around #6 coil to keep any moisture out. once all dry the car ran fine and has ever since, knock on wood. I seem to think that this is possibly a problem with the design as we both had the exact same thing happen at the exact same mileage, moisture should never get down in the coils....hope this helps others out there!

I have a 2000 Duratec as well, with 56k on it also. Weird, but i had the exact same thing happen about 2 months ago. Engine would misfire causing a "bucking" feeling which scared the hell outa me. Computer read that #6 was the one. After also seeing water on the plug i replaced it. 3 days later....same thing. After that i took out a heat gun and heated up the coil from #6, as the duratec's do not use the normal plug and wire, but instead coils. after heating it, i swithed #5 and #6 applying tape all around #6 coil to keep any moisture out. once all dry the car ran fine and has ever since, knock on wood. I seem to think that this is possibly a problem with the design as we both had the exact same thing happen at the exact same mileage, moisture should never get down in the coils....hope this helps others out there!

I seem to be having the same issue with 54000 miles! Where is #6 located on the 24v Duratec? I'd like to try the hairdryer fix.