3.5 EB spark plug design update ‘22+

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catinthehat85

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I’m also curious just got a misfire code after a tune, down pipes and FMIC I have about 18k on my 22 I was just going to change plugs I bought some off SPD but they do not have the gasket. Doesn’t anyone know if the tapers will work if not I’ll be sending these back and getting OEM ones
You can always use a borescope and check them yourself for a tapered seat, only thing is I don’t know if plugs can be reused like that. If nobody has an answer here by the time I’m ready that’s probably what I’ll do.
 

svt54

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@mook5186

I work at one of the Ford plants and reached out to an engineer at the Cleveland Engine plant that builds the 3.5 ecoboost. The change of going to the flat washer gasket plugs and indexing was done for fuel efficiency reasons. This change was done to all the 3.5s in the Raptor as well as the regular F-150. He said the tapered cut is still there, but they added an additional flat cut for the washer gasket. He told me there is no issue using a tapered seal plug in the new head.

I installed a set of NGK 95605 in my 23. They installed fine and are one step colder. That said, my particular mis fire issue has not been resolved by the plug change. I am on an e50 tune, IC, BOV. Truck runs and drives great under normal conditions. It pulls like a freight train at WOT throttle too, BUT at WOT, usually in 4th or 5th gear I started getting intermittent misfires. It's a coin flip on wether I get enough to trigger a DTC and do the 30-second cylinder shutdown. The DTC is nearly always P0303 (cylinder 3 misfire), but occasionally will be P0305 or P0306 (cylinder 5 and 6 respectively). On an earlier revision of my tune, with less boost and slightly less timing I was able to run with 0 misfires. That said, The current revision I am having the issue on is not crazy amounts of boost or timing. I am below what lot's of trucks have run successfully.

So far my troubleshooting has been:
swapping coils around to see if misfire moves (it doesn't)
changing to the NGK plugs
re-gapping the NGK plugs to .024
re-gapping the NGK plugs to .020
Stretching the springs in the coil pack boots by about a quarter of an inch to insure good contact

I hope the plugs correct your misfire issue. So far, I am still chasing mine. If you figure it out, please post up and let us know.
 

catinthehat85

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@mook5186

I work at one of the Ford plants and reached out to an engineer at the Cleveland Engine plant that builds the 3.5 ecoboost. The change of going to the flat washer gasket plugs and indexing was done for fuel efficiency reasons. This change was done to all the 3.5s in the Raptor as well as the regular F-150. He said the tapered cut is still there, but they added an additional flat cut for the washer gasket. He told me there is no issue using a tapered seal plug in the new head.

I installed a set of NGK 95605 in my 23. They installed fine and are one step colder. That said, my particular mis fire issue has not been resolved by the plug change. I am on an e50 tune, IC, BOV. Truck runs and drives great under normal conditions. It pulls like a freight train at WOT throttle too, BUT at WOT, usually in 4th or 5th gear I started getting intermittent misfires. It's a coin flip on wether I get enough to trigger a DTC and do the 30-second cylinder shutdown. The DTC is nearly always P0303 (cylinder 3 misfire), but occasionally will be P0305 or P0306 (cylinder 5 and 6 respectively). On an earlier revision of my tune, with less boost and slightly less timing I was able to run with 0 misfires. That said, The current revision I am having the issue on is not crazy amounts of boost or timing. I am below what lot's of trucks have run successfully.

So far my troubleshooting has been:
swapping coils around to see if misfire moves (it doesn't)
changing to the NGK plugs
re-gapping the NGK plugs to .024
re-gapping the NGK plugs to .020
Stretching the springs in the coil pack boots by about a quarter of an inch to insure good contact

I hope the plugs correct your misfire issue. So far, I am still chasing mine. If you figure it out, please post up and let us know.
Thank you very much for the info! Sorry you are having this issue, I am also on e50, no issues though.
 
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