2002 ford

I have a friend that has a 2002 ford expedition, He says that while it ldles it has a miss fire. He has had it put on a machine the Tech told him to change out the # five & the # one plug. Now he told me that he has changed out all of the coil packs, plugs, boots, fuel filter, vaccum lines, he has a hunderd thousand miles on the motor. I think it might be a valve sticking or a cam lobe worn, So if anyone might know what it could be hit me up.

Change out pcv, idle air control valve and clean throttle body. Then clean engine with a can of seafoam for sticking valves. Go with full synthetic oil for optimum engine protecting. Hope this helps!
Franco

I have a friend that has a 2002 ford expedition, He says that while it ldles it has a miss fire. He has had it put on a machine the Tech told him to change out the # five & the # one plug. Now he told me that he has changed out all of the coil packs, plugs, boots, fuel filter, vaccum lines, he has a hunderd thousand miles on the motor. I think it might be a valve sticking or a cam lobe worn, So if anyone might know what it could be hit me up.
i have a 99 and had same problem it was actually oil leaking into my spark plug boots do to leaking valve cover gaskets replaced v cs and got my truck back to running better than ever.