For a few weeks only when it was wet out we would get a p0302 misfire code. As the engine warmed up it would go away. Figured it was a cracked coil pack. Just to be sure i switched the drivers side and passenger side packs and it then would misfire on p0306. Opposite side. Thinking that it now moved to the other side when i switched coil packs that was it. Wrong. Now i got a p0306 and p0305. I put the new pack on each side with no changes. Put each orginal coil pack to each original side and am now getting a p0302 code. What is going on here?! Each time it misfires the cat would smell. Before as it warmed up and stopped misfiring the cat smell would go away. Any help?

Are the coil packs grounded through each of the 4 mounting bolts? I have only been putting 2 bolts in to keep it in place til i get it figured out.

 

2 brand new coil packs didn't fix the problem. It is now showing a p0306 which is cylinder 6 misfire, and a p1151 code. Where do i go from here?

 

Check the wiring to the coil pack. Make sure it's plugged into the harness good and makes good contact and isn't corroded badly. Check all your vacuum lines for leaks. Might have hit something when swapping the coils.

 

Have you replaced the wires ? Ck the plugg wells for moisture ? Changed /checked the plugs ? If getting a " rolling " miss there may be moisture in the plug wells , or bad wires and plugs .

 

Plugs and wires were done 80k miles ago. Is there a module that fires the coil packs or is it the PCM?

Expedition has 265k miles.

 

I too would take a good look at the 2-wire connector going to the COP.

 

I am going to replace the wires. What brand ones should i use?

 

Use OEM wires if you plan on keeping the truck, or auto part store brand if you're not.

 

Cheapest place to order factory wires?

 

Cheap and factory do not go hand in hand together.

 

I also hate to bust a bubble , but ... If changing wires , or plugs , you need to change both . Especially after 80k . Wires take a thermal set to the plugs . You can solve a wire miss ( for a bit ) to have it return .Change the wires and plugs . Go with Motorcraft plugs and wires .Most Good parts stores sell them .