CoreyMS

There's no way a tool could get around the top of it. Mine were never that hard.

gwpfan

I know since you said even more miles, but going back and re-reading some of your posts I see you were gapped at 0.32 on the plugs before, did you ever try running the previous plugs at 0.30?

Mine still idles rough while in drive and stopped at a stop sign/light. Mine are gapped at 0.33-0.34, they were 'factory' at 0.38-0.42, ran smoother once re-gapped just debating going tighter gap or just changing to the 2013 style as you've done.

crash_ice

I just installed new plug in my EB .
I called the dealer and said i want the 2013 plug.
My original plug are CYFS12Y3 OR LTR6AI-9
My new Plug Are CYFS12Y-T3 OR LTR6CI-8 or SP-534.
i go for 2 hour ride now and give feeback but the idle seem more smooth.
Of course the dealer gap all the plug to 0.30.

CoreyMS

This is what I'm seeing on the 534s as well. Idle seems smoother, the plugs are gapped at .30 in the box. I want to say my mileage seems better (aka maybe .5, but my truck has always done okay on gas) but I do realize the temperature has been a lot warmer which is most likely the better reason.

crash_ice

I just came back for a ride and it feel smoother on idle and on the road .

I think the plug of 2011 and 2012 are not good

Smokey1

I have a 2011 F150 FX4. Had my first real misfire/hesitation with flashing CEL at 62k kms, took to shop, and they replaced Coil and plug on cyl 2. Few weeks later, same issue, with some online research I assumed it was due to the CAC issue, had both recalls done. Issue remained, was throwing a p0300 and p0303 last time I pulled the code and was dealing with Ford Canada to either get me out of the truck or replace the ignition system.

Last week I found this thread, called the dealer and ordered the 534's. Installed them today, 91k on the truck and it has been gettting progressively worse, breaking up all the time, any WOT runs would always buck and miss. Swapped the plugs today, all of the end plugs were gapped at 0.045", and the two middle were 0.040". After installing the 534's it runs perfect, no miss, no hesitation, full runs up to 140-150km/h with absoultely none of the previous symptoms. I only got a few kms on it today, but I will update with mileage in the next few days. I'm quite happy that my truck may finally be fixed, no thanks to Ford or their engineers. Am I ever glad I didn't trade it in for a 5.0, after a short test drive I realized how primitive it is in comparison.

CoreyMS

Yes, ran the original stockers at .30 for almost 5000 miles. Honestly tighter should make idle worse, everything else equal. At this point I'd suggest the sp-534's. They come .30 and were 27 bucks.

sluggo1

Amazing to me how this is actually the cause of many people's problems yet Ford swears it was a mysterious intercooler condensation issue. Ford should be a bit embarrassed if the fix is as simple as a change of plugs or gap.

MadocHandyman

I wonder how much is a varying combination of the two? Those with the worst condensation and plugs/coils has the worst time.
Me, I never had the limp mode issue, just the shudder. It was reduced by re gapping my plugs but it didn't fully clear up until I got the new CAC.
Those with less condensation buildup and good ignition maybe don't experience the issue until their plugs or coils start going bad?
It is strange that some do it, some don't and some don't experience it until thousands of miles of ownership.

oricko

I have a 2011 ecoboost with the miss or sluggish feeling around 80-85km under slight load.
The dealer sent mechanic on a test drive with computer and he said it was the waste gates spooling when they should not be. Dealer is insistent that it is a moisture problem, I feel it is more likely a bad waste gate. So I was wondering if that is not the same problem some of you are having.