Gas Mileage
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- Third Gear
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Those of you getting less than the originally rated fuel economy, are you sure that everything is in tune and you're not lacking in maintenance. Good o2 sensor and what not?
If everything’s in good shape and you're economy hit isn't because of your right foot, do you know if the fuel you buy has ethanol in it? I'm sure you've heard on the news about the push from many Midwest states to require corn based ethanol in the mixtures of gas. If the car is built for it, this could be a good thing (though the jury is still out on the concept). Cars like ours though were not built to for this. The biggest thing is that the stoichiometric point is changed when ethanol is added to the fuel. This means that the calibration to our o2 sensors will be off as the ethanol blend burns leaner than regular gasoline. The result is the computer richening the mixture and therefore causing poor fuel economy. Recent studies suggest the hit on fuel economy could be as much as 30%.
It might be worth your interest to find local fuel that does not use ethanol or to at least find out if your fuel does. I’m working on a few solutions. Some have used xelene in their fuel to correct for the extra oxygen in the fuel. This also helps octane as well, but may be cost prohibitive. I’m testing out an o2 interpretation device with my wideband that might work. Oxygenated fuel hits the northeast about this time of year. Ethanol will be the oxygenating agent as they no longer use MTBE. I’ll let you know if/how it works. I just happen to be using my Subaru as the test rig
If everything’s in good shape and you're economy hit isn't because of your right foot, do you know if the fuel you buy has ethanol in it? I'm sure you've heard on the news about the push from many Midwest states to require corn based ethanol in the mixtures of gas. If the car is built for it, this could be a good thing (though the jury is still out on the concept). Cars like ours though were not built to for this. The biggest thing is that the stoichiometric point is changed when ethanol is added to the fuel. This means that the calibration to our o2 sensors will be off as the ethanol blend burns leaner than regular gasoline. The result is the computer richening the mixture and therefore causing poor fuel economy. Recent studies suggest the hit on fuel economy could be as much as 30%.
It might be worth your interest to find local fuel that does not use ethanol or to at least find out if your fuel does. I’m working on a few solutions. Some have used xelene in their fuel to correct for the extra oxygen in the fuel. This also helps octane as well, but may be cost prohibitive. I’m testing out an o2 interpretation device with my wideband that might work. Oxygenated fuel hits the northeast about this time of year. Ethanol will be the oxygenating agent as they no longer use MTBE. I’ll let you know if/how it works. I just happen to be using my Subaru as the test rig

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90L Wagon EJ22E on Toyota CT-26 boost -- Crushed!
95L Wagon on T3/T4 boost :)
www.trdsupra.com [b][url=http://trdsupra.com/library/forsale/]Cheap parts![/url][/b][quote="Imprezive"]alright, I give up, I'm going to NASIOC...[/quote]
Re: Gas Mileage
how is your tank so much bigger? I get less than 300 to a tank but ~27 mpgscottzg wrote:I just did some all freeway driving, and i got 410 miles on my tank of gas. I was using 87 and averaging about 80-85 mph the whole time. That works out to about 25mpg. Is that about what everyone else is getting? I have a manual NA sedan.
Oh, and this is added, i get about 360 city, that works out to be 22.5.
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Re: Gas Mileage
holy quoting 2 years ago, batman!tzedek wrote:how is your tank so much bigger? I get less than 300 to a tank but ~27 mpg
I think i did the math in my head?
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