Regular vs Super

[Camry1999]

Hey Everybody,

So, I want to the Toyota dealer to talk to make some copies of my keys & I was just talking to the guy @ the service dept about the difference between the PZEV Camry's & the ones w/out that rating & I mentioned that my friend's '04 Camry LE that my friend gave me while he was away in India gives me about 27 MPG where as my '05 Camry LE gives me 22 MPG. I told him that I put in only super in my car & he told me that there is no difference between the Camry's w/PZEV emissions & the ones w/out. But he said that super burns quicker so you will get less mileage. Is this true? Can someone please shed some light on this problem? Thanks in advanced.

[Buurin]

If you are talking about gasoline grades, it's said that regular burns sooner/easier than super, so much that in FI or high compression engines regular gas would start burning before it's intended to, aka detonation.

What he may be seeing is less ethanol in super gas than regular gas - that is said to drop your gas mileage by 2 mpg or so. People on cleanmpg sometimes go to great lengths to find pure gas, but I recently ran a tank of Shell V-Power (it's "supreme" gas) which claims to be ethanol free, and I fail to see a difference.