Truck started shuddering, threw p0302.. I will start with plug wires, they are 12 years old.. if that does not work, can the coil packs be swapped with each other? Other than plug, wires, and coil pack, could there be anything else that would cause this?

 

Loss of compression will cause it as well.

 

You can swap the coil packs.

 

Start with a basic tuneup of plugs and wires.

 

These trucks are very sensitive to plug wires. Use only Motorcraft replacements. Coil packs are fairly cheap to replace; I bought Excel units.

Jim

 

New wires seems to have fixed it for now... I wanted to remove the plug for cylinder 2, but after backing it out it only about a half a turn, it did not want to seem to budge.. I didn't want to damage anything so I left it in... Is this something that anyone has experienced? The plugs have been in there for 12 years, although they have only about 35K miles in that time...

 

Spray down plug well with WD-40 or some kind of penetrant. Let it sit for several hours; let engine totally cool down.

Turn plug in all the way, then back out till you feel resistance, then try to go a little more. Then screw plug back in till loose, and repeat this process. Take your time and go by feel.

Jim

 

WD-40 is not a penetrant, use something like PB Blaster or the like.

Most likely, there's a build-up of carbon on the bottom threads of the plug. Spray some own in the plug well, loosen the plug a bit, work it back and forth a few times, then let it sit with the plug out as far as possible so the liquid will go down to the last threads and have a chance to work on the carbon deposit. Repeat several times as needed.

Worst case is that the threads get damaged and you end up needing an insert to repair it. Try to avoid that!

 

Thanks, I figure carbon buildup on the lower threads as well... When I change them next I'll have to take my time and use PB blaster and repeated tightening/loosening as suggested...