Check your owner's manual. Mine is a 2004 GTP and likes premium, but regular is okay and won't damage it . . . only downside is the engine puts out less power . . .
the lowest octane fuel that still gives proper combustion delivers the most power and best fuel efficiency. pontiac did its hw and whatever it says to use will give optimum performance. should be on the gas cap or in the owners manual.
you can run regular if need be, no it wont have as much horsepower, but in this day and age if u need to save the extra cash does horsepower matter that much?
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