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Engine misfire on no.7.

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Need help. I have a 2015 6.2 that's throwing a Po307 code. Misfire on #7.swapped out the coil, spark plug, and wire with cyl.3. Erased code on startup immediately set code again. Any thoughts on what's next. BTW it does have 103000 miles on the clock.  TIA

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Had the same thing on my L86 at 125K miles.  Miss on number 7 it was a bad lifter.  Now I have a stage 2 TSP cam and DOD delete because of it.:thumbs::driving:



I also had a miss on #5 at 115K miles.  That was a broken valve spring but It didn't drop the valve so it was a cheap and easy fix.


Don't drive it anymore and pull the valve cover off of the drivers side NOW.  It's easy to do.  Lets know if you have any questions about it.

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2 hours ago, Larry Cooke said:

Thanks again for all your help. I'll get it in the shop tomorrow and pull the valve cover. I'll let you know what I find. 

Did you do any misfire tracking leading up to this, or was it basically hard fault stored and now you are looking into it?



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