Currently have 66xxx on my 2016 Eco and runs great. Have been diligent about preventative maintenance. However one thing I haven’t changed are the ignition coils. Have swapped the plugs every 15k but not touched ICs.

I have no issues of misfire, hard start, etc. should they be replaced at any specific interval or only when an issue arises?

thanks

 

Coils should last the life of the vehicle; change them if they're not working. The maintenance schedule in your owner manual calls for replacing spark plugs at 100,000 miles.

 

Leave them alone, especially if you have no issues!

 

However, spark plugs and boots are worth considering at that mileage. Use a generous dab of dielectric grease on the boots when you reinstall them.
https://www.rockauto.com/en/moreinfo...10150&jsn=1076

 

Swap plugs every 15k miles??? WHY?

Last time I swapped plugs at that mileage was back when my vehicles had points/condenser ignition.

 

I was thinking the same thing. Changing perfectly good plugs at 15K miles makes no sense. I think my first car 40 years ago, required 30K plug changes.

 

.
While you have taken impressive care of your vehicle and obviou8sly have had good luck, there is no advantage to replacing items unless there is a proven need.
Plugs at 15K are no where near ready to replace on a practical >non competition basis< unless there are cylinder issues affecting the Plugs such as Oil, Super Charging etc..
Coils have been greatly improved over the years for quality and life over the older ones of the early 2000s. Like anything mass produced, there can always be occasional failure, the same as Tires and other maintenance items that are replaced on failure or end of service life.
When Coils fail, you will get the codes P030x or P035x for the cylinder in fault.
And can use s Scanner to look at Mode 6 data storage of misfires for every cylinder to even look ahead before total failure might occur..
Just comment that may be considered.
Good luck.
,

 

just asking: if either are bad wouldn’t there be a miss?

 

Certainly. If either a coil or plug has gone bad, it's usually obvious. Plugs have a finite lifetime, and on my 3.5 I changed them at about 60-65K, but coils should last much longer. I've only ever had 1 or 2 go bad since they became the norm.

 

Thanks all for the information. I assumed only replace coils if one causes a misfire or other issue

as far as the plugs, not sure why I replace them so often. I must have read where the eco boost can eat them up. It seemed to with my 2012 I had. Since I just put these in at 60k, I’ll let them go longer.