Misfire code cylinder #7..new coil and plug still misfiring

Houselr

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Check engine light comes on, I get the code read and it is a 307, misfire on #7 cylinder. I replaced the coil and the spark plug. Still runs rough and light comes on. I changed the coil on the third cylinder from the front on the driver side. Any suggestions.
 

Yupster Dog

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It is misfiring all the time and wiggling it did not make it stop.
(I know you said you just put new coil and sparkplug on 7)

Remove the coil pack and spark plug on 7 and switch with 6 to see if the misfire moves.
 

amoreno

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If it keeps misfiring after a sparkplug, coil and cable replacement, make sure the injector is correctly installed/working properly. If it keeps misfiring after that, I'd suggest you to check Cylinder # 7 roller followers. For more details, please watch the following video:

 

Anthony DeVor

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You should be able to unplug the coil plug harness on #7 and move it to the adjacent coil plug and see if it follows, if it doesn't then it could be a compression or fuel issue.
 

Yupster Dog

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You should be able to unplug the coil plug harness on #7 and move it to the adjacent coil plug and see if it follows
A For effort but them brain farts will get you.

@Anthony DeVor if you do that then the cyl you change with will be sparking when#7 should be firing and vice versa.

This will not work and not a good idea to even try it.
 

John A Petty II

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This may sound silly, and I am NOT a mechanic, nor claim to know a lot about cars...
But, perhaps check your catalytic converter?
I know, given the advice above, seems from left field, but,
I have 2015 Exp XLT with just under 70k. I had bouts where the engine would sputter, misfire and lose all power after hard acceleration. In the worse instances I would need to pull over and pause and restart and it would "seem" fine. Eventually, on a rainy night recently, I accelerated hard and the engine blew. My mechanic was at a loss as all seemed otherwise okay (prior to the incident).
Shortly after getting the engine replacement, I stopped in for a requested "follow-up look-around" and he pointed out another Exp, 2016 in the shop, ALSO for a engine replacement!
He noted on that one though, the catalytic converter was clogged. He asked if I had experienced any of the symptoms I noted above, and then noted that if I had brought it in I could have possibly avoided a needed engine replacement...
Your noted misfire issue reminded me of one of those symptoms, and with no other obvious cause, can't hurt to at least look...
Best of luck, I hope it helps, if not you, somebody else!
japii
 

purevw

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Number 7 miss is often a tossed rocker. I wasted a lot of time checking many things before I found it is a common problem. The pic is of my 2011 Expy. Rocker was $14 and gasket set was $54 a year ago. I think I gave $35 for a Ford valve spring compression tool set. I was fortunate that the rocker found a solid perch and did no further damage. There is a very good mechanic on YouTube that works on Fords. His videos are very well made. I only replaced the single rocker, which may be bad practice, but I have 50,000 miles since it was done with no hiccups. If this is your issue, check the cam lobe very carefully for scoring, as well as look around for other physical damage. I'll add one caution. The back screws on the rocker cover can be a booger to get to without exactly the right tools. I used a 1/4" drive with a swivel extension.

2020-10-04-Roller-Rocker.jpg
 
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