So I picked up an 05 F150 in January with the 5.4 3v. I know about the plug issue. I'm at 93k miles and I know I need to do the plugs, but I'm hoping I can get away with just the COPs for the time being. My issue is that at low RPMs between 45 and 55, if I start to ease on the gas (not enough to down shift) to speed up, the truck misfires and shakes. If I ease off the gas and get back into it, it's fine. At speeds of 60+ this doesn't happen.
Now I'm confused, because it never throws a CEL. Researching more I decided to find someone to look at the mode 6 data. All cylinders passed. Cylinder 3 shows one single misfire, but this is a daily thing so I don't see how that's possible. I replaced the coil on #3 just to be sure, but no help.
Any ideas on what to do short of plugs?
Now I'm confused, because it never throws a CEL. Researching more I decided to find someone to look at the mode 6 data. All cylinders passed. Cylinder 3 shows one single misfire, but this is a daily thing so I don't see how that's possible. I replaced the coil on #3 just to be sure, but no help.
Any ideas on what to do short of plugs?