We have a 2017 Explorer with the 2.3 EB with a little over 62,000 miles. We bought it new. Thank goodness for inline 4 cylinder engines when it comes to changing spark plugs. Cylinders 1 through 3 were creaky dry upon removal but came out just fine. Cylinder 4 wasn't as creaky and I found out why, oil on the threads, but not on the firing end of the plug. All the ceramics were light tan, even #4. The gaps were all .030, well within the .027-.031 Ford spec. I replaced them with the recommended Motorcraft plugs, SP-537/CYFS-12Y-2 Iridium plugs. I gapped the new plugs at .027. For a turbo DI engine I was pleasantly surprised how little wear there was at 62,000 miles on the plugs. They could have easily gone much further wear wise but I was leery about removing them at the recommended mileage without having a difficult time. I used anti-seize and reduced the torque 15% from the suggested maximum.
2.3 EcoBoost Spark Plug Change
- Thread starter Whimsey
- Start date
Good idea to change plugs on EB engines. They start to misfire under high boost, even if not worn out. 60K miles is the outside limit.
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They look good! Those Motorcraft iridiums are NGK ILTR6G8G
Are you going to replace the spark plug tube seals?
Are you going to replace the spark plug tube seals?
Thanks for sharing. I have the same engine in my 2015 MKC and was recently advised to do a tuneup as the car reaches 60,000 miles. I thought it was a classic dealership trying to drum up business recommendatio, but now I’m not so sure
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- Feb 27, 2019
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Thanks for sharing. I have the same engine in my 2015 MKC and was recently advised to do a tuneup as the car reaches 60,000 miles. I thought it was a classic dealership trying to drum up business recommendatio, but now I’m not so sure
I think most platinum iridiums are good for 100K miles, don't know if that's what you have in your MKC.
However, it also depends on your driving style. Do you spend tons of time idling? If so maybe look at getting them done earlier. If you don't notice anything with your vehicle you may be fine still.
I think they would use the same plugs, given they are the same engine, just 2 years apart. We don’t do a lot of idling, but do a fair amount of shorter trips these days...
I should have stated the driving conditions these plugs experienced. My wife drives 50 miles RT to work 4 days per week, mainly local highway and interstate, not a lot of local traffic, some bumper to bumper occassionally. But on her days off anything goes. We use the Explorer for our driving vacations, so that is highway also. They wore great but I didn't want them to be difficult to remove at 100,000 miles of use.
the issue with boosted engines, is that the boost will actually Blow out the sparked fuel !! A friend of a friend just picked up (for$500) a Pontiac GTP, and he had some small issues under load. My recommendation,new plugsc
there are enire discussions on anti-seize. The 'nickel' on the plug is anti-seize. Adding anti-seize theoretically can lead to mis-fires
i have seen fine print on plugs specifically stating not to use antiSeize compound
It only leads to a misfire if it is misused... don't glob it on all ham fisted. Even nickel coated plugs that require no "doping" with anti-seize will cement themselves in a head of non- similar metal. Give them just a smudge of anti-seize, always, but nowhere near the tip of the plug... that's what causes your misfire...mis-application. 
Recent tune up on a chevy truck used Denso iridium plugs. I followed the packed in instructions as to *not* using any anti-seize as the plugs are already coated. I put them in dry, torqued to spec. Later, diagnosing a cylinder misfire? I pulled the plugs. They were absolutely locked into my aluminum heads after only 7k miles. After they were pulled, they went back in with just a scoche of anti-seize nickel. A following month later, after finding the issue with a burned up coil pack, another misfire led me to a companion cylinder coil that failed. But this time when the plugs came out to "read" them, they came out slick and easy.
I don't care what plug manufacturers recommend. Just a dot of anti-sieze on the threads keeps you from wondering if a diagnosis/tune is also going to cost you $1600+ in heads. :/
Oh, and check your valve cover spark tube gaskets. SUPER easy enough on any Ford inline-4 power plant. A boosted engine will have all sorts of back and forth pressure and vacuum internally. A weak set of gaskets will just blow oil out any which way it can. Check/ replace your PCV/orifice too.
Recent tune up on a chevy truck used Denso iridium plugs. I followed the packed in instructions as to *not* using any anti-seize as the plugs are already coated. I put them in dry, torqued to spec. Later, diagnosing a cylinder misfire? I pulled the plugs. They were absolutely locked into my aluminum heads after only 7k miles. After they were pulled, they went back in with just a scoche of anti-seize nickel. A following month later, after finding the issue with a burned up coil pack, another misfire led me to a companion cylinder coil that failed. But this time when the plugs came out to "read" them, they came out slick and easy.
I don't care what plug manufacturers recommend. Just a dot of anti-sieze on the threads keeps you from wondering if a diagnosis/tune is also going to cost you $1600+ in heads. :/
Oh, and check your valve cover spark tube gaskets. SUPER easy enough on any Ford inline-4 power plant. A boosted engine will have all sorts of back and forth pressure and vacuum internally. A weak set of gaskets will just blow oil out any which way it can. Check/ replace your PCV/orifice too.
