I have a 05 Legacy turbo. The iridium spark plugs have a replacement interval of every 60k miles. I recently had a 60k service performed and for whatever reason they were missed. I inquired with dealer(service writer) and they stated most they find are great condition and would perform at 90k(about 1.5 year from now).
The car does run perfectly and achieves the same mileage as always. What are the downsides or damage that can occur from aged plugs?
Damage to the engine most probably none. The car can come up with misfires before it reaches 90K but the good side is that these plugs are expensive and for now you have been saved from the expense.
Over and over we advise people to follow the schedule in the owners manual. Just for thought, if you go to change plugs at 90K and one is stuck Dealers going to say "service interval is 60K.
Over and over (and correctly so)we advise people that Service Advisors are not technicaly competent
Did you get a labor reduction on your 60K service because the plug replacement was skipped? Don’t let them say “labor for 60K service is x dollars no matter what is done”. Check your invoice.
According to their “menu” of services I definitely was not charged and even charged less than menu price for whatever reason.
If you turn down anything they note it duly on the bill that customer turned down X which is not the case here.
I honestly do not love the service department but do not pay for it either since I use coupons that are a kick back from my credit card.
Those plugs are expensive, especially from the dealer. Since they see a lot of these engines so they probably know what they are talking about. If you were not charged for the labor to install them, call yourself lucky and be happy.
Those iridium plugs are expensive, but the possibility of damage to the cylinder heads if the plugs become fused in place is potentially even more expensive. If I were you, I would have the plugs changed at your next oil change. Just whip out another one of those Subaru Bucks, and you won’t have to pay much.
Don’t you just love those rebates? I pay for everything possible with my Subaru Mastercard (even my utilities) and usually have at least $200.–$300. of those certificates sitting in my service file, just waiting for my next major service.
Ask the Dealer,“if the plugs become frozen will you pay”. Put them on the spot. In some circurstances we call the Dealers idiots and ripoffs and in other we say they know what they are talking about and they are just trying to save you money.
I can’t for one minute fell comfortable telling a customer to leave his plugs in longer than the manufacture recommends. In fact when GM says leave them in for 100K you mechanic should advise you about the danger of this.