I'm still working on getting out the bugs on my 04. Terrible mileage this morning, some bucking at low rpm overdrive, and a faint smell of gas, but no CEL. I took it to oreilly on my break, set the parking brake, put it in reverse, and started pulling the COP connectors. 1, 2, 3, 5, and 8 were fine. 4 was too far to reach on my work break, but 6 and 7 were on and off. The first time I pulled 6, the truck didn't drop in rpm's. Put it back on and no change. 7 was fine at that time. As I checked again, 6 was fine, but 7 made no change to rpm. I went back and forth with this for awhile until it seemed like both were working correctly. Drove it down the road and the low rpm buck was gone, no more smell of gas, and the truck was more responsive. Gas mleage on the stock lio-o-meter was much better.

Will COPs that are crapping out switch themselves on and off like I described.

Obviously, I am going to change them, but is that normal behavior for COPs crapping out?

BTW, mods to truck are Gotts intake, K&N drop in, spark plug change, and max inflated tires. I have my mark VIII efan at the house and am just waiting for my DC controller.

 

What did you put in for spark plugs? Which engine?

 

Sorry. 5.4 Engine. SP507 Motorcraft plugs.