Jim says:
> I'd
>suggest backing down one grade from premium(R+M/2=92) and try a
>midgrade(R+M/2=89).  Listen closely for pinging under hard accelleration,
>like up a hill.  If you hear any, go back to premium.  If not, thry the
>regular(R+M/2=87) grade and listen for pinging again.  

This raises another question....the mid-grade and high-grade gasolines, i.e.
R+M/2=89, 92 (at least here in Nebraska), are generally 10% ethanol. My
owners manual says to steer clear of alcohol blends. Why?

Pat
____________________________________

Patrick L. Larsen
Water Center/Environmental Programs
University of Nebraska
pll@unlinfo.unl.edu
http://www.uvm.edu/~plarsen/pat.html
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