John Paul, AAA Northeast's Car Doctor, answers a question from a reader wondering whether they need to follow the ...

Most states have the option of choosing octane ratings of 87 (regular), 88–90 (midgrade) and 91–94 (premium). But in a few states, the gas pumps look a little different. “It’s mainly ...

Is premium fuel worth the extra cost over regular ... However, if a driver mistakenly puts 87-octane regular in a vehicle that needs 91 or more, the engine-control computer should be able to ...

Whereas 93 octane is the common premium fuel in the Northeast U.S., West coast drivers operate the very same vehicles on 91 (often the highest octane available), with no particular ill effects.

The system features a pair of fuel injectors for each cylinder, one providing 91-octane pump gas for subdued driving and the other for high-octane race gas while under increased boost pressures.