I just changed the plugs, and the ones I removed were Autolites. They were stamped '985', but there was no 'AP' or 'APP' preceding it. Do the APP985's have that on them?
I doubt the plugs I took out were bad, since the Jeep only has 58K on it and they weren't original. I'm pretty sure my misfire codes will go away though. Whoever put them in, gapped them at .025. All the places around here had to special order APP985's, but I found Champion 7034's.
Hopefully, the mileage will be better than 12-14 mpg now. Sure runs smoother.
2005 Wrangler TJ, 6 cyl, 6 speed, only mod (so far) is a little bigger tire (31x10.5). I wasn't expecting to get good mileage, but 12 sounded a little low.