Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - I want to get to the bottom of this ethanol killing my mpg

Nerys · 01-24-2010, 03:20 PM

I am correct on rich. Please read before replying.

The math says I should see a 3.5% drop in FE with ethanol. I am seeing IN EXCESS of 20%

does this not mean I am running RICH for some reason? Stoich according to you folks means 3.5% below normal FE.

SO my assumption was that for "whatever reason" the ethanol makes my car run rich (though it does not throw any codes)

since its using MORE FUEL than the math says it should be under the conditions.

Can't really have water in a well used fuel tank. Water is heavier than gasoline so it will sink to the bottom and be the FIRST thing your fuel pump draws in with nasty consequences I imagine.

Since this has not happened I imagine this is not my problem.

and yes I drained all of the fuel tanks when I had to change the fuel pumps. the insides appeared normal. No obvious wear rust or residue rather clean actually which I guess makes sense since your running gasoline through it.

I fill up twice a week usually. or twice in roughly 8 days or so. so any phase seperation would have to happen pretty darned fast :-)

I am going to go get some mid grade gas today and try my hand at removing the ethanol and "see what happens" it will be expensive but it will get me some data to work with.

Who knows maybe its not the fuel but I am having a tough time figuring out what could possibly be affect SO many vehicles in precisely the same way.

The only thing I can think of is all of my ECU's became corrupt in exactly the same way at exactly the same time resulting in exactly the same FE loses?

Logic says BS to that :-) but I won't outright dismiss it.

If I manage to find another XFI ECU I can afford (very rare mind you) I will get it and install it and "see what happens"

For me energy efficiency has ONE valid description in this discussion. How many miles can I go on one gallon. Thats it. Nothing else matters to me.

If your a race car driver OK you want HP if your town 10,000 pound trailer cross country OK you want HP

ME I just want as many mpg as I can get per gallon which also means the lowest dollar amount per mile driven. any other description of efficiency is just not that important to me.

01-24-2010, 03:20 PM	#167 (permalink)
Nerys Grrr :-) Join Date: May 2008 Location: Levittown PA Posts: 800 Cherokee - '88 Jeep Cherokee 90 day: 19.44 mpg (US) Ryo-Ohki - '94 Geo Metro Xfi 90 day: 50.15 mpg (US) Vger 2 - '00 Plymouth Grand Voyager SE Ninja - '89 Geo Tracker 90 day: 30.27 mpg (US) Thanks: 12 Thanked 31 Times in 25 Posts	I am correct on rich. Please read before replying. The math says I should see a 3.5% drop in FE with ethanol. I am seeing IN EXCESS of 20% does this not mean I am running RICH for some reason? Stoich according to you folks means 3.5% below normal FE. SO my assumption was that for "whatever reason" the ethanol makes my car run rich (though it does not throw any codes) since its using MORE FUEL than the math says it should be under the conditions. Can't really have water in a well used fuel tank. Water is heavier than gasoline so it will sink to the bottom and be the FIRST thing your fuel pump draws in with nasty consequences I imagine. Since this has not happened I imagine this is not my problem. and yes I drained all of the fuel tanks when I had to change the fuel pumps. the insides appeared normal. No obvious wear rust or residue rather clean actually which I guess makes sense since your running gasoline through it. I fill up twice a week usually. or twice in roughly 8 days or so. so any phase seperation would have to happen pretty darned fast :-) I am going to go get some mid grade gas today and try my hand at removing the ethanol and "see what happens" it will be expensive but it will get me some data to work with. Who knows maybe its not the fuel but I am having a tough time figuring out what could possibly be affect SO many vehicles in precisely the same way. The only thing I can think of is all of my ECU's became corrupt in exactly the same way at exactly the same time resulting in exactly the same FE loses? Logic says BS to that :-) but I won't outright dismiss it. If I manage to find another XFI ECU I can afford (very rare mind you) I will get it and install it and "see what happens" For me energy efficiency has ONE valid description in this discussion. How many miles can I go on one gallon. Thats it. Nothing else matters to me. If your a race car driver OK you want HP if your town 10,000 pound trailer cross country OK you want HP ME I just want as many mpg as I can get per gallon which also means the lowest dollar amount per mile driven. any other description of efficiency is just not that important to me.