05 mountaineer missing

no codes have shown up no check engine light driving down road at any speed it will jerk a little changed plugs wires and coil pack still does it a lot worse in damp weather any ideas

Which engine does your Mountaineer have? When you changed the plugs, did you notice any spark plugs that looked different from the others? Also, regarding diagnostic codes, did you check for pending diagnostic codes or only active codes? There could be a pending code for a cylinder misfire or lean/rich code that is not yet active.

Have you also checked the intake air tubing to make sure there are no cracks in the tubing and that it is connected properly? You might also want to clean the MAF sensor.

-Rod

its a 4.0 all the plugs looked the same when they were changed i took them all out again yesterday and they all looked fine havent checked intake tube for cracks but i will the maf sensor has been cleaned and havnt checked for pending codes thanks