2016 edge, changed spark plugs and coils w/91K (pics)

[volk06]

Our 2016 edge with 91k and the 2.0L ecoboost started running rough last couple of weeks at start up for about 30 seconds and on Thursday my wife called saying it was running really rough starting up and finally threw a code. I was expecting to replace the evap purge valve based on symptoms but the code I pulled was P0304, cylinder 4 miss fire. Ordered new Motorcraft plugs and denso coils and got them all swapped out today. Very easy to swap out. Took me an hour taking my time and torquing to spec.
Fired right up and is now running good (for a while now hopefully).

I was already planning to buy new plugs for this and the fusion, I researched the cost 3 weeks ago and was planning on swapping them out this summer but the code beat me to it. OEM normal service interval is 100k.

When I pulled the #4 plug, it wasn’t as bad as I was expecting but the gap was significantly open. 1 and 2 had a lot of carbon build up. I usually run a gumout regane or Techron before an oci at 5-10K ocis, depending on the oil.

All of them pulled 1,2,3,4 in order.

Number 1

All the carbon falling off.

Number 4

 

[KCJeep]

Surprised they didn’t give you problems before now. Sounds like 100k was a bit optimistic.

My sons old Sebring went 160k before we figured out they had never been changed, but it wasn’t a turbo either.

 

[Dave9]

Your money to spend, but there was apparently no need to replace the coils, especially when (I assume?) you don't have to take the intake manifold off to get to them? At least you used Denso instead of some generic. I wouldn't throw out the old coils in case you need them someday.

100K is optimistic, some make it that long and others don't.

 

[Sierra048]

Just curious. We have a 2021 Edge. I have looked at a lot of the maintenance items I will have to contend with when the time comes. One of the plugs (left to right the fourth plug) is partially covered by the high pressure fuel pump. Did you have the same problem, and if so, can you tell me how you dealt with it? Question to any member: Does the fuel pump retain pressure all the time or does it let up after sitting for a while. It's nowhere near time for me to deal with it but just curious as to what to expect. Thanks.

 

[92saturnsl2]

Other than having been in use for 90K, I see nothing wrong with those plugs that would contribute to a misfire. I think the coil was your culprit here, just not sure why you replaced the other 5. A new coil can go bad just like any old one.

 

[volk06]

Your money to spend, but there was apparently no need to replace the coils, especially when (I assume?) you don't have to take the intake manifold off to get to them? At least you used Denso instead of some generic. I wouldn't throw out the old coils in case you need them someday.

100K is optimistic, some make it that long and others don't.

Denso makes the motorcraft coils so figured might as well save 50% and get Denso instead of the motorcraft.

Did I need to replace the coils? Maybe, maybe not but I wanted to get it all done at once since I was already going to be working on it. Getting an hour to myself to fix things is a rarity for me now days. Online forums with similar codes, the coil was 50/50 the problem. It wasn’t that much more to just do them. From my experience, when one goes bad, the others aren’t far behind and it’s a roll of the dice when they go bad.

 

[zzyzzx]

I would have like to see an old and new spark plug in the same picture. Those plugs look like they potentially could have been cleaned and regapped.