Hello all,
I have a 2002 F-250 with a V-10 motor. lately it seems to studder, sometimes almost buck, around the 45-50 MPH range, it seems more apparent when it is wet or humid (no check engine lite on). I am assuming that it is electrical but I really dont know where to start. I changed the plugs but I dont want to swap out all of the coil packs, is there a way to test them individually? I had a similar issue with my F-150 but that was solved with a transmission flush and filter change, not the case with this one.
Any Help will be appreciated!

 

Take it to a shop and they can do a power balance test. That will check if a cylinder is not firing all the time and which ones are the problem. My V10 had 2 bad coils, replaced with a 10 pack from eBay and everything is fine.

 

Your rubber boots over the plugs may be cracked causing a misfire when water falls into the plug opening. I would replace all boots and use good amount of dielectric grease.