Coil packs

[Dry-fly]

I have an ‘07, V8 4Runner… she’s got approximately 240k on the original ignition coils. There’s no stuttering or misfiring but I could swear my mpg’s are down. The usual tune up stuff has been done. Do these things “wear out” or do they run till they just break. (Referring to the ignition coils). Thanks all.

 

[88Center]

Expected run on those is 100-150k miles.

Mine are still the original and I'm at 180k. I plan to replace them at 200k, along with new spark plugs.

Spark plugs I do every 40k or so.

 

[Dry-fly]

Yeah, they have lasted plenty long for sure. My question though is do they start to wear out… do they deliver s weaker spark towards the end of their life, or do they work 100% until they don’t? Make sense?

 

[SocalSam]

Whatever you do, use Denso or OEM. Aftermarket are cheaply made and will not go the distance. Personally, either they work or they don't. If you suspect coils, do misfire count on your scanner. Misfires can occur intermittently and may not set CEL.

 

[MikeinNH67]

How old are the plugs? As mentioned, the OEM specified plugs have way less miles allowed than most current vehicle plugs. Also, as Sam mentioned, no cheap aftermarket stuff or you will be chasing other troubles. I'm doubtful it's the coils causing the MPG issue as they usually work well or start getting troublesome which will show as a stutter under load. You could pull them and do a visual inspection plus ohm them out looking for oddities. For MPGs, you can try cleaning the TB, MAF and such.

 

[Buckaroo]

I have an ‘07, V8 4Runner… she’s got approximately 240k on the original ignition coils. There’s no stuttering or misfiring but I could swear my mpg’s are down. The usual tune up stuff has been done. Do these things “wear out” or do they run till they just break. (Referring to the ignition coils). Thanks all.

I do not think they degrade - they fail due to a break in the windings. It can come and go, perhaps with temperature but you would see misfires. Colder weather with longer warm up times and winter gas are two reasons why you might see lower MPG this time of year. Degrading performance of upstream oxygen sensor or MAF could contribute to lower MGP.

 

[Dry-fly]

Thanks all for the replies. Absolutely would only be using Denso parts. Everything else has been done maintenance wise. MAF was cleaned. Plugs are fairly new. Air filter is clean. Yada, yada. All that had me wondering if the ignition coils could be suspect.