Hello!! I have a well running 2009 Toyota highlander that has 120K and is due for new spark plugs. This is just being done for maintenance purposes, haven't noticed any problems. The mechanic told me no problem and will replace with iridium Denso plugs. However, I explained I wanted to also have the ignition coils done with the job and he told me 'well, there's no use in doing that. Just replacing the plugs will do'. I'm not going to argue with him, it is saving me lots of money, but is he right or do I run the risk of having ignition coils issues soon? Basically, what is the life cycle of these ignition coils?
Listen to your mechanic. Leave your coils alone (unless they show symptoms of failure)..
Ok, will do. Only reason I hesitate is because last year I had 2 coils go bad in our 2009 Corolla, about 1 month apart each and I was like 'ok, guess coils don't last forever and I will replace them as maintenance'. But I can't find anything definitive about that. Just a coincidence I had to deal with the same problem a month apart?