Date: 3 Feb 1999 06:53:57 GMT From: saab85900nopsamcom (Saab85900) Subject: Re: 93 9000 gas mileage low - why
>bulwnkl wrote: >Sounds strange, doesn't it? It's not at all true, of course. >Oxygenated fuels are typically either (up to) 10% ethanol or (up to) >15% MTBE (Methyl-Tertiary-Butyl-Ether). Now, if the fuel in question >was 15% MTBE, and if MTBE had ZERO potential energy released by the >combustion process (that is NOT the case), then a 10% mileage drop >would be at least in the ballpark. However, MTBE has only (very >roughly) 10-20% less available energy than gasoline. Therefore, a >10-20% loss on 15% of the fuel translates to a 1.5-3% potential power >loss. Only part of this will be observed as reduced fuel economy, >though. The rest will simply be degraded performance. So, relax; it's >just an old wives' tale I guess I must be an old wife, then. In our area, we did so well on the oxygenated gas that we don't have to have a special winter blend--get the other all year long. And when I get out of town and purchase gas that isn't oxygenated, my mileage goes up about 10%. Dick in Falls Church, VA