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On another forum they are recommending spark plug changes for the ecoboost engines every 15,000 miles?? Surely this is not right. One person stated at 55,000 miles his spark plug gap was at 0.50 instead of 0.32
The owners manual says to replace at 100,000 miles for my 2017 2.7l. Unless it is tuned or you are getting rough idle and/or poor fuel economy, I see no reason to replace them before hand.
Heres how the story went..back in 2011 3.5 people were having misfires. I was deaf to it as I was following the 100k deal and Iridiums were still new and were to outlast platniums...
Somewhere in the warranty period ~30k I started getting cold fire misses that were so bad they stared setting misfire codes and the truck shock violently. I took it into the dealer when it reached this level, at first here we were thinking that even though the misfires were there and you could feel them, it needed to be bad enough to store a mis fire code, so off to the dealer I went. light came on.
So from the dealership after a week, they confirmed cold misfire, grossly at start up. I told them to keep it to make sure they got right. the week they called and said it was back(or never gone to begin with). so they want to try coil next. Another week elapsed and they said it wasn't the coil, so now they want to replace fuel injector(I believe by here they are off track and cant recover). So I told them go ahead and replace the injector, they had to get the removal tool so I wait later. After another week they supposed replaced fuel injector. I got the truck back after a month, it worked for another 10k miles. That cylinder started misfiring till I traded it in with over 100k on it.
Moral of the story, there was something wrong with that cylinder at about 15000 it would start misfiring and I would replace that plug and the rest. The truck would scat with new plugs in it. I didn't replace the coil boots until around 70k which helped as well. I actively persued aftermarket coils but for $500 bucks that wasn't going to happen. Ok I am a n **** person when it comes to my trucks, so oil analysis every OC. Fuel dilution was acceptable every time and wear metals came in at 30k(after I figured out the leaking unsealing airbox cover-another story).
I use my fuel economy and senses to detect mis-firing. At 15k on this 2016 I am getting idle misfires-but not enough to misfire codes. it has lost some low end grunt as well, and doesn't pull up hills like it used to when new the trans wants to downshift to 5th on the same hills that used to pull 6th all the way. I have plugs coming and will report back then.
Heres where most everyone is missing it(including Ford engineers), everyone is blaming the IC from excessive moisture content into the cylinders which is blowing out the ignition and causing misfires...
Heres whats important and sorry to bring it to light but I will: when the water ingestion contacts the 2000+degree temps in the metal combustion chamber and then the porcelain, it doesn't recover, it cracks and now you get arcing, the plugs are not self correcting. At this point it needs plug replacement! So the damage is done every time you get midfires caused by the moisture problem..
Heres the second problem with this, the IC is not the problem, its the poorly engineered PCV system that dumps mass quanity of water into intake. Don't believe me go to youtube and search of the system and see how many OZ. water they are catching with just a catch can. A cup per oil change!
So until the PCV system design is addressed and not so much the IC system, the 3.5/2.7 ECO engines will be hard on plugs(eat them)..Now if someone tells me they are running a catch can/PCV redesign I would believe that their plugs would go longer then 20k interval, but now with it being boosted its still going to eat plugs, then program it on top of that, with more boost and more advance and not the right fuel and that would be one plug eating mama!
I am still learning and figuring out this stuff as well, so I don't know all, however I am very knowledged in auto design, repair, and modification for over 40+yrs. and used to make my living off of troubleshooting machinery. So do yourself a favor and get out there and replace your plugs if you have more then 40k, have ever had water ingestion, chipped, beat on your truck, or for me like getting 26-27mpg. They are easy to do and WELL worth the investment.
Sorry for the extended rave and hope this help people to understand the unengineered systems and wear points of the ECO engines.. reply and prove me wrong if you don't concer.
Last edited by Mach 1; Sep 26, 2017 at 05:39 PM.
Reason: RB
The maint guide is recommendation and differs according to driving habits, climate, fuel quality, dirt/offroad driving conditions just to name a few. Then that goes out the window when modifications come into play...I.E. exhaust, programming, intake changes, even things such as oversize tires.
I would much rather pick up info for several places then just one to make a more informed decision. But I do it my way and pull them and see how they are holding up. anything out of the normal operation, which people don't observe and the fall off is over a year so the detection has to be vigorous. Most people just drive them and don't worry/monitor the condition......what do they say drive more worry less.
I changed the plugs in my 2.7 at 55K and found one with a cracked insulator. All gaps were right around .03. Installed new plugs and truck is much happier. My catch can catches a decent amount of crap, not much water, mostly oil.
Last edited by funnyman06; Sep 26, 2017 at 09:53 PM.
Ecoboost Spark Plug
