Do I use regular unleaded or unleaded plus if I live in a mountain state? See details.
My owners manual states I should use gasoline with a pump octane rating of at least 87 octane. In most places this is regular unleaded, but I live in Colorado and the octane rating for regular unleaded is 85 and plus is 87. Apparently mountain states gasoline has a lower octane rating than other states. Does this mean I have to use unleaded plus in my 2006 Elantra?