From what I was told think like putting the car in neutral coasting down hill will not incease mileage like it will if you just keep it in gear with the fuel cut off.

 

DON"T BUY A TORNADO! My girlfriend got me one for my old '98 Saturn. It got an average of 37mpg before the Tornado was installed. It then averaged 36mpg after. The car had throttle body injection. Buy a Tree Air Freshener, it'll be better use of your money & it's cheaper!

 

For those readers out there, Popular Mechanics did some testing on "miracle fuel savers" and pretty much came up with the same conclusion, but with more technical detail.

http://www.popularmechanics.com/auto...32.html?page=1

 

I put three Tornados on my car, and I have to drain off the excess fuel twice a week.