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Random Misfire F150

Ford has had this problem since they went from waste spark to CoP, or since 1997. Between bad coils, a bad coil driver, poor plug thread engagement, 3 piece plugs...you couldn’t get me to trust one. Some models are more prone but there is something amiss in their R&D when it comes to ignition issues and it can keep you chairing your tail. Any particular rpm it is happening at, load conditions, etc.?

I get the stutter or shudder on a hard acceleration. Normal driving conditions I don’t have any hesitations

It feels harder than any other “skip” I’ve ever experienced in other vehicles

It’s done this before on a hard acceleration but check engine light never stayed on, it does now though
 
Mine's an '04. Had two coil packs go bad coming home from Mississippi. Felt like the transmission was about to fall out of it. Stopped at a dealer in Scottsboro, Alabama, $450 later, it's runs like a new one. Said they had to change the two plugs under the bad packs because they foul when the packs go bad.
 
Wish I could datalog it for you, then you could get a count on which cylinders it’s doing it in and how often. That said, usually multiple cylinders don’t experience this problem unless you have several weak coils, old/improperly gapped plugs or a fuel delivery issue.

If you haven’t changed the plugs yet, or if you did and are running platinums I would suggest changing to iridiums. DI is harder on plugs I’ve found, especially without an additional injector upstream to help wash any fine oil mist that makes it back into the intake tract and adhere to the intake valves which leaves carbon deposits, such as GM’s 3.6 DI engines. I always add an external catch can to combat that issue.

Next would be the coils if I had to guess, if they’ve been fighting to jump the gap because of erosion of the tip they could have been weakened and as discussed, coils have long been a known bane in some of Ford’s OHC engines.

Beyond than it could be a fueling issue but Ford has had good pumps and with the inclusion of the filter/pump being in the tank it would be a pita to check, as long as pressures are good I would worry about this last.
 
Had exactly the same issue. Brother in law changed them today. We took the factory plugs that are gapped at .032 and gapped them at .028. Studder is completely gone and is running like new. Hope this helps.
 
Had exactly the same issue. Brother in law changed them today. We took the factory plugs that are gapped at .032 and gapped them at .028. Studder is completely gone and is running like new. Hope this helps.
You have the ecoboost?
What year?
Can you reach the plugs without any special tools?
 
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