wxman wrote:It's the same with the 2010 owners manual. But the dealer definitely said regular was fine...didn't even make an issue, he said "it uses regular." I was surprised to see what the manual said. Most of the info I've seen supports the dealer....you can use regular in almost any car except a turbo. If there is a decrease in performance I haven't noticed. There is a rather steep difference in price between regular and premium, and so the only thing I really want to know is am I doing any long term damage. if not, I'll stick with regular. And, yes, I can "afford" premium but I don't think using premium gas is a status symbol, just a waste of money if not needed.
I meant that I think the owner's manual agrees with what your dealer said... using regular is ok and shouldn't cause damage. And the reason it shouldn't cause damage is that the engine timing will be adjusted to prevent knocking, at the expense of a little performance (or maybe gas mileage).
Here's an article that discusses it (not specific to the EX or Infiniti, but the general idea):
http://www.caranddriver.com/fe...ature
Modified by sg77 at 3:49 AM 3/28/2010