Originally Posted by JCL

I agree with you on the ethanol issue, it is a sad state of affairs when we are using food crops to make our cars run more poorly.

In reference to your comment that premium doesn't matter, that isn't what the original poster asked. The question was whether 87 or 91 matters. I suggest that it often doesn't, but better fuel sometimes has more cleaning agents, and I agree with you that it sometimes doesn't have ethanol (the 94 AKI I purchased today had zero ethanol, unlike all the other fuels at that particular station). Both the cleaning agents and the reduced ethanol are reasons to choose more expensive fuels, which usually means fuels that have a higher AKI.