About a year ago I replaced the COP on cylinder #4 after the code came up that it was missing. Then about a month ago the truck start running awful again and the engine light comes on with the code P0354. I ordered a new COP from global automotive, but this time changing it did not get rid of the problem. I took the truck into the mechanic and he said the COP boot was too long and not making contact with the plug and needed new plugs and COPs (which I definately do) But here's my real issue, he said that one of the the COP's had backfed and fried a quad in the computer. Is this possible?? I need to make a decision after the weekend...

 

I'd change the plugs and get the right coils (DG508's for an 01) then see how it runs. I've never heard of that happening but you never know.

 

Who knows what you installed there. Sounds to me like you shouldn't be the one ordering parts for your vehicle lol.

Never heard of one back-feeding, but only you know what you did, well maybe?

 

I installed a global automotive COP that was suppose to be for a 2001 F-150, but I think he sent me the wrong one. But the one I replaced a year ago seemed to work fine for about a year and then started missing again.

 

Yea, we need more info. Like a part #. PO354 is total primary failure. #4 is a dead hole. And thro #1 coil into #4's slot for now. Ignition integrity plays a roll with these trucks IMO. If a coil fails within an aged system, the rest soon follow suit.

What to keep in mind:

Although replacing all coils in a dedicated COP system is advised, like all electrical components, there's still the chance of getting a bad one out of the box. Coils are so cheap from the RIGHT distributer, ordering their 10 packs can pay off. Mishaps happen, so it's nice to have a few spares.