I have read all the threads about misfiring and they all seem to be the same. From change the COP to carbon build-up. I tried putting in new plugs, swapping COPs, cleaning injectors, etc. The only thing that nearly worked was replacing the COP. It worked for about a week and again with the misfire. So I gave up and took it to the dealer and expected to dorp my pants and take it up the... well anyway... They told me it was the #2 COP and I nearly flipped because I had already replaced it with a new one. So they replaced it with a Ford OEM COP and not the Autozone generic and now no more problems. I of course paid $125 but what I found out is that our truck NEED OEM parts only! So dont waste your time and money on generic parts and buy the right ones the first time and save yourself a HUGE headache.

- Chuck

2002 4.6 XLT supcab

Complete Alpine audio System
-2 10" type S
-2 750watt alpine digital amps
-4 4x6 type S components
-Alpine XM
-Alpine MP3/cd/xm deck

Magnaflow true dual exuast with 3" Chrome tips
K&N Air Charger
Line-x
Ranchhand toolbox and grille guard

 

I have used an aftermarket COP for the last 30 K miles on an 01 Excursion. I have driven from Charleston, South Carolina to Miami, Florida and from Charleston to Alaska (and back to SC both trips) with no problems. I don't know why you had a problem with an aftermarket COP but I believe they are good quality parts. I will continue to purchase them (if needed). Of course the dealer would like everyone to believe that only "genuine" Ford parts will work. I would like to hear of experiences with aftermarket COPs from other vehicle owners.

 

Sure some parts work just like pig parts have worked in humans... but in my experienced I have had better luck with OEM parts.

- Chuck

2002 4.6 XLT supcab

Complete Alpine audio System
-2 10" type S
-2 750watt alpine digital amps
-4 4x6 type S components
-Alpine XM
-Alpine MP3/cd/xm deck

Magnaflow true dual exuast with 3" Chrome tips
K&N Air Charger
Line-x
Ranchhand toolbox and grille guard

 

I replaced all my coil packs with what I thought were OEM packs. The box had "Motorcraft" painted all over it. When I examined the COP, I found that "Motorcraft" was not printed on the top of the COP. Regardless, the new COPs work great, and have been working great for months. I seriously doubt that there is that much difference between OEM and aftermarket COPs. I would bet that the aftermarket manufacturer sells them to Ford with the "Motorcraft" label on them.

Chuck -One thing you didn't mention was whether or not the Ford tech replaced both the COP and the plug or just the COP. Theytypically replace both, at least thats what they told me at the dealer. I have heard where a bad plug has caused the COP to fail.

Anthony