ffffpsh

Hello fellow forumers,

I changed the plugs in my 2012 ecoboost last night. I ordered pregapped .32 motorcraft oem replacement plugs from amazon. After replacing them I received the horrible shudder under power and the engine went into limp mode on the highway. I had never experienced a shudder like that before with the truck until changing the plugs. I measured the gap in all the old plugs and most were close to the .39-.42 area.

I will check all my connections tonight but maybe I got a bad plug? Either way, is there a nicer "gapless" (2+ prong) plug that people use in the ecoboost with positive results?

Thanks,

Your fellow annoyed EB owner.

Gremlin85

I've never recommended any other spark plug other than the OEM's. The Motorcraft plugs are better than anything else out there that you could put in there with the exception of maybe NGK.

With that said, it is not uncommon for people installing the plugs to have possibly over-torqued or angled the socket when tightening to where it cracks the porcelain. This could be a possible reason to your stuttering and limp mode.

Another could be a plug not torqued down all the way or even the boots on the COP to have been damaged or not correctly installed. Then possibly the electrical connectors as a final reason.

I'd go back and check all connections, inspect how the COP sit. After that, if everything looks fine, I'd take out all the spark plugs and make sure you didn't crack the porcelain on any and make sure they are all tight.

Check back with us after you do this if you cannot find your problem.

Boostking

Dont go gapless. The motorcraft plugs you have are fine. You could have possibly torn a boot or not got the coil correctly down on the plug. Might be a simple misfire if you are sure you torqued them all correctly. Did you get a CEL or any codes to read?

ffffpsh

I got a flashing CEL and the truck cut all the power when I got the shudder. I have not pulled the negative terminal so it may say why it is still in limp mode? The flashing light went away after about 4 minutes of driving it like a baby.

I didnt move the tube over top the driver side furthest forward coil when removing and may have bent it too far trying to get it around that tube. Ill swing by ford today and grab a new one. I torqued them with a wrench at 10.5 ft/lbs and was very cautious due to all the threads I have read about handling the plugs.

Thanks for all the help. It is nice because the problem is easy to diagnose because the shudder was barely noticable before and now it shakes the whole truck after doing the plugs so it has to be something related to that. Plugs in very vehicle I have ever owned have been very straightforward and always made the cars run better.

Boostking

Yeah I think you likely cracked a plug or the COP is not on correctly or damaged. Thankfully like you said, it should be easy to diagnose. I cant remember the tube you are talking about, but if its some sort of air balance tube and its pinched, that could lead to some strange behavior.

If it were me I'd just re-do the whole job to retrace my steps and see if I messed something up. Since you did get a flashing CEL and limp mode, you should have a DTC stored that can be read. I bet its a misfire and might tell you the cylinder. If you dont have a code reader find a friend with an SCT device, or go to Autozone, or get a bluetooth OBD2 reader and Torque for Android.

ffffpsh

I went out and read it on my lunch break. Misfire cylinder 2. Im a dummy and forgot to read the specific code before I cleared it and gave it another go. Correct me if I am wrong but cylinder 2 is the passenger side middle cylinder?

again, thanks for the insight and tracking this down. It seems like it is a quick fix but i was very "mcclaren production line" methodical and careful when I did it. I couldn't imagine having broken something myself.

Oh well! Ill report back with what I find for anyone referencing!

Boostking

I know the firing order according to the PCM is 1, 4, 2, 5, 3, 6. As for what cylinder it is I'd have to try to find it. 2 should be the middle on one of the sides lol.

Found this:

Cord

There is a TSB out that addresses the boots failing. Here's a thread: https://www.f150forum.com/f70/ecoboo...ug-tsb-308705/

ffffpsh

So my thoughts on that are...
1) I had no issues with it before plugs. So it is a plug/electrical oriented issue caused by myself or the new plugs during the install procedure.
2) I heard many cases of power loss with the TSB.

3) The ONLY thing I can think of that would be beyond the install itself is if the truck doesn't like to run on .32 gapped plugs which from my research, is not normal. Usually the trucks run better w/ .32 plugs.

ffffpsh

I sorted the issue out last night.

I went to advanced auto yesterday over lunch and some highschool kid with the obdII scanner was able to give me both the codes and the cylinder number off his handheld. I decided to swing by ford to pick up the parts on my way home. I pulled into the service center (you can buy parts in the service center) and asked the service rep if he could read the misfire i was having. He grabbed his scanner and hooked it up. He proceeded to tell me that his scanner can't find the codes and that I need to bring it in for a diagnostic/tune up. Kind of sad that a retail auto store can retrieve more accurate and deeper information than a ford dealer at first shot. Made me lose a bit of faith in my dealer.

TLDR - I replaced the coilpack (w/ boot) and plug in cylinder 2 which was the middle passenger side, pulled the neg terminal on battery and hooked everything back up. It ran like a charm!

Now I am going to snag a catch can!