I want to get to the bottom of this ethanol killing my mpg

[Old Tele man]

...blending his own blend of blended fuel!

[Frank Lee]

Not only that, but we have new blending pumps in our town, where you can select E10, E20, E30, and so on.

[shovel]

I run E85 in my s10 and my Tempo. Both have custom ECU firmware and the S10 has an updated fuel injector assembly (no more lame poppets) - running E85 in the S10 pushes me up to +24 fuel trim but that's still within range, no CEL.

They love it. There is a drop in MPG when using E85 vs. straight gasoline and a huge increase in HP. I notice no drop in MPG when using "oxygenated" gas vs. "100% gasoline" .

No fuel pump replacement yet...

[Frank Lee]

My F150 seems to like E85 even better than my Tempo. Neither have been modded for E85 one iota so they'll throw CELs when they max out the fuel trim. One difference is when the fuel trim gets back "in range" the CEL goes out right away on the truck, but it stays on in the Tempo until I do a key off/key on cycle. The CEL seems to come on less in the truck anyway on E85 so I suspect it is programmed to be able to go a skosh richer than the car.

[99LeCouch]

You can always dose your gas with 4 oz/10 gallons of TC-W3 2-cycle oil or Marvel Mystery Oil. Some people have shown gains in FE with those additives. They are supposed to restore lubricity to the fuel. And they're pretty cheap per tank.

I do know MMO works quite well at quieting down your fuel system, running it in my car right now. No data on increased FE yet.

[Nerys]

Hey maybe its not the ethanol. I am by no means close minded on the issue but all the data I DO HAVE conclusively says it is.

My Tank to Tank FE readings are rock solid. That was a point I was trying to make. I went over 200,000 miles in the cherokee with hardly ever more than 2mpg change in FE. usually less than 1mpg difference tank to tank.

In my van over 50,000 miles rock solid 18-19mpg (I drive the same route the same time the same way 3-6 times a week)

I also had that freakish incident when we started ethanol here where I would hunt down the non eth gas stations and always be back up to 18+mpg

The trick is how to I prove its ethanol OR prove its NOT ethanol. the only way I know to do this is to really really test it IE get some non ethanol gas.

Clearly the year of the vehicle is not the issue since you guys are using 90 and 93 vehicles without a problem.

as for the fuel pumps. What else could cause ALL of them to fail in such a short time? and I do mean ALL of them. the only vehicle I have no replaced the pump on is the Thing and thats largely because I have not driven it in 3 years

Suggestions?

[NiHaoMike]

Originally Posted by shovel

I run E85 in my s10 and my Tempo. Both have custom ECU firmware and the S10 has an updated fuel injector assembly (no more lame poppets) - running E85 in the S10 pushes me up to +24 fuel trim but that's still within range, no CEL.

They love it. There is a drop in MPG when using E85 vs. straight gasoline and a huge increase in HP. I notice no drop in MPG when using "oxygenated" gas vs. "100% gasoline" .

No fuel pump replacement yet...

Have you tried lean burn with E85? You don't even need a different oxygen sensor. Just program the firmware to lean out the mixture at constant throttle and periodically switch back to stoichiometric in order to check the ratio with the oxygen sensor.

[silicon_toad2000]

I just wanted to check with the OP, are you sure you're getting a gallon for every gallon you're charged for.

Here in oz there were a few tests done on random service stations and a few were found to have pump which supplied just less than a litre for every litre the pumps said that it pumped.

Might be worth checking, some of those cheaper stations need to do everything they can to stay afloat.

[Nerys]

The difference I am seeing is pretty big and when I have filled say a 5 gallon tank it seemed pretty accurate.

also here E85 is more expensive than Regular. $2.01 for Regular $2.19 for E85

[SleeperRT]

Good posts, this is a hot-button issue of mine. I think Ethanol is getting a bad rap at the way it's being introduced. It's a flat different fuel than gasoline, same as diesel (from gas). I hate flex fuel engines because they get crappy gas mileage on ethanol. It'd be like making an engine to run on gas or kerosene, it might be OK on one, but it will always suck on the other. They're just different.

I was bummed in your first post when you installed a new engine. I was bummed you just installed a new engine rather than doing a rebuild or a custom build (I understand the cost problem though). Ethanol has amazingly high octane ratings, much like the leaded gas. For emissions our compression ratios have come way down from the 13:1 in '73 to a more 8-9.5:1 from then to now, though it is going back up. Since ethanol has 20% less power per same quantity of gas, when you run it, your computer simply pumps 20% more fuel into your engine (that's very simplified). This is where the fuel mileage reduction comes in, more intake means worse FE, and more exhaust means hotter manifold temps.

If you want to truly resolve the issue, you would need to build the engine to only run a specific version of ethanol, E85 is great for cooler climates, E100 doesn't start in the cold so they add gas which is much better for this. You would need a higher compression ratio to fully take advantage of the higher octane. An ethanol specific cam would be nice. But the main issue would be having a custom tune done (this is where carbs are nice for me).

Great points, you are fully hitting the bullseye on my problem with the flex fuel thing going on. Alternative fuels are just not gas. Ethanol is not a miracle fuel. But we need to get off gas, so whatever path we decide on I wish we'd just commit and go with it. The so-so approach on anything is not helping public perception, IMO.