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Old Jun 1, 2019 | 09:58 PM
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2015 3.5 ecoboost
What would cause misfire on cylinder #3?
2015 3.5 ecoboost 71000 miles
 
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Old Jun 1, 2019 | 10:16 PM
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Are they the original spark plugs?
 
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Old Jun 1, 2019 | 10:19 PM
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Originally Posted by JKBrad
Are they the original spark plugs?
Yes they are!
 
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Old Jun 1, 2019 | 10:42 PM
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3.5 EBs are notorious for wearing out plugs. Most here agree to change them at 40-50k miles. I'd say you got good service from yours. Ford claims 100k miles, but in reality they just don't last that long.
 
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Old Jun 2, 2019 | 05:43 AM
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Joe nailed it on the head and addition to the plugs, ensure you change the boots at the same time or you'll likely do it all over again with multiple misfires.
 
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Old Jun 3, 2019 | 05:39 PM
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So what seems to be causing this issue my old 5.4s had over 100000 not one issue.
So how are the 5.0 for this issue?

thanks
 
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Old Jun 3, 2019 | 05:53 PM
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Direct injection
 
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Old Jun 4, 2019 | 07:44 PM
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Originally Posted by REDFORDFX4
Yes they are!
Should be on your second spark plug change by now. They burn out quickly and are known for carb tracking. Don't forget to change the boots.
 
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