info on E 85 tune

[Jackpine]

Originally Posted by Sburn

FFV Taurus use a sensor in the fuel line that measures the optical property difference between gasoline and ethanol and is able to tell the PCM about that percentage. PCM can then manage fuel and timing for any mix between 100% gaoline and 100% E85. I'd assume that FFV F150s likely use the same scheme, but I have no first hand experience.

Nice point, Sburn! I vaguely remember someone posting that there WAS a sensor somewhere, but I don't think I ever saw anything more about it (so it got filed in secondary memory).

It really makes sense doesn't it, that if one of their vehicles has the sensor, all flexfuel ones would have it? I guess Bill would know for sure, or, perhaps one of the techs on the forum?

- Jack

[Sburn]

Originally Posted by JackandJanet

Nice point, Sburn! I vaguely remember someone posting that there WAS a sensor somewhere, but I don't think I ever saw anything more about it (so it got filed in secondary memory).

It really makes sense doesn't it, that if one of their vehicles has the sensor, all flexfuel ones would have it? I guess Bill would know for sure, or, perhaps one of the techs on the forum?

- Jack

OK, so I did a little digging on this starting with my 2007 Ford F150 Wiring Manual and the Powertrain/Emissions Manual. No mention of a separate FFV sensor in either. Only slightly different wires for fuel pump and fuel gauge with FFV options are shown. NO PCM inputs for a FFV sensor.

So more digging on Google seems to suggest that Ford went away from the fuel line-style FFV sensor sometime around 2000.

Looks like Ford now does the calculations all in software with the only hardware change being a wideband oxygen sensor in place of a narrow band oxygen sensor in front of the catalytic converter(s).

Best as I can wrap my noggin around it at this late hour is that the PCM, via the wide band O2 sensor, always tunes air/fuel ratio for a lambda of 1.0 A lambda of 1.0 indicates complete burn, irrespective of the fuel used. So with the PCM software always tuning the AFR for a 1.0 lambda for whatever gas/E85 mix is being burned, you get a Flex Fuel Vehicle pretty much via software.

[Jackpine]

Excellent post, Sburn. Of course the closed loop lambda of 1.0 takes care of everything! I hate it when the "obvious" is right there in front or me and I don't see it! My stupidity really amazes me sometimes. :o

And, in case anyone missed it, Sburn just explained that there is no specific tuning needed for changing from "real" gas to the E85 "fake" stuff.

However, Bill can certainly modify the way fuel is delivered to provide even more performance gains over "stock" with this stuff, just as he does with real gas.

- Jack

[Sburn]

Originally Posted by JackandJanet

Excellent post, Sburn. Of course the closed loop lambda of 1.0 takes care of everything! I hate it when the "obvious" is right there in front or me and I don't see it! My stupidity really amazes me sometimes. :o

- Jack

Yeah, took a while for it to "click" with me, too. I'm still unclear how open-loop (cold start & WOT) mixtures get handled. I assume PCM uses a static map for that is rich for E85 and really rich for gasoline under the assumption that the open-loop operation won't be happening for long. But that' s just my guess.


I think in an earlier E85 post, I stated that the Feds mandated E85 to the auto makers. I believe that happened, but it sounds like Detroit didn't shed too many tears about it. From a 2006 "Car and Driver" article"

"With fewer than 600 stations selling E85 fuel in 37 states, why have GM, Ford, and DaimlerChrysler been cranking out these flex-fuel vehicles by the millions?

The answer is the mandatory Corporate Average Fuel Economy (CAFE) standards. Federal law requires that the cars an automaker offers for sale average 27.5 mpg; light trucks must achieve 22.2 mpg. Failure to do so can result in substantial fines. However, relief is available to manufacturers that build E85 vehicles to encourage their production.

The irony here is that although E85 in fact gets poorer fuel economy than gasoline, for CAFE purposes, the government counts only the 15-percent gasoline content of E85. Not counting the ethanol, which is the other 85 percent, produces a seven-fold increase in E85 mpg. The official CAFE number for an E85 vehicle results from averaging the gas and the inflated E85 fuel-economy stats.

Calculating backward from our test Tahoe's window-sticker figures (which are lower than but derived from the unpublished CAFE numbers), we figure the E85 Tahoe's CAFE rating jumped from 20.1 mpg to 33.3 mpg, blowing through the 22.2-mpg mandate and raising GM's average. What's that worth? Well, spread over the roughly 4.5-million vehicles GM sold in 2005, the maximum 0.9-mpg benefit allowed by the E85 loophole could have saved GM more than $200 million in fines. That's not chump change, even for the auto giant"
From:

http://www.caranddriver.com/reviews/...stuff/(page)/1

[Jackpine]

That Car and Driver article is really an "eye opener" isn't it?

I keep hoping, now that we have someone who is scientifically trained in the Dept of Energy, (at least I think we do?) we might just finally move forward in this process of converting sources of energy into useful results. I think the Engineering Community is up to the task, if they can just get a little incentive and the resources to forge ahead.

And, I believe you are correct regarding open loop - the fueling is taken off a map that probably tries to be the best of "both" worlds. Since E85 has a much richer ideal A/F ratio, (and it's possibly less prone to ignite?), I think you're dead on too about the mixture being VERY rich for a flex fuel vehicle running real gas at start. Personally, though, I'm quite surprised at how long it takes my truck to come out of open loop after start (I can tell it has because the torque converter will suddenly lock up).

I imagine this could be an area where Bill's custom tunes would really stand out. Since WOT is also open loop, he could tweak the fueling to be appropriate for the particular fuel used - rather than tuning a compromise.

[Sburn]

Originally Posted by JackandJanet

I keep hoping, now that we have someone who is scientifically trained in the Dept of Energy, (at least I think we do?) we might just finally move forward in this process of converting sources of energy into useful results. I think the Engineering Community is up to the task, if they can just get a little incentive and the resources to forge ahead.

I have no doubt that the Engineering community is up to the task. My fear is that politics will continue to get in the way of rational, scientific, and data-driven discussions.

Politicians seem unaware or unwilling to discuss the decisions that need to be made regarding the trade-offs required for different sources of energy, or in the development of new sources. And our-less-than scientifically literate public tends to gravitate to the latest “fad” touted by those political or economic factions that might be operating under a different agenda.

E85 was a good example: “Cheap fuel from domestic corn and we don't have to worry about that rotten OPEC.” Sounded real good when it was put that way, but E85 didn't work out very well unless you were selling fertilizer to farmers, sucking up subsidies, or trying to get elected in the farm states. And the fact that growing corn and using it for fuel instead of food was bound to end badly.

Hydrogen was quite the fad a few years back until this pesky little thing called “Physics” got in the way. “Run your car on hydrogen and the only thing that comes out of the tailpipe is water...” was the pitch. After all the ribbon-cuttings, and and photo ops, and all the grant money spent, even little Timmy in grade school figured out from watching the experiment with a battery, water, and two inverted jars, that it took just about the same amount of energy to make the hydrogen as what was provided by burning the hydrogen.

I fear electric cars like the Chevy Volt won't end up catching on either. First, you have to plug it in, so that electricity has to come from somewhere. I'm personally OK with building nukes or mining coal to add to the electrical generating capacity, but I don't think a majority of our fellow citizens are ready to deal with that trade-off yet. Next, you have the lithium battery problem. There's only a couple places in the world to get lithium, with most being in South America. And right now, the sole source of those GM batteries, and lithium-ion batteries in general, is South Korea. If Great Leader in N. Korea keeps getting chippy, we got another international problem.

No matter what the source of energy may be, the final issue may be wide-scale implementation. Right now, Toyota Prius and Chevy Volt, and whatever else comes down the pike, are only available to those who are fairly well off. Get stuck in the morning commute in a major city and you will find yourself surrounded by all the rest of the folks driving $2,000 “beaters” to the daily salt mine so they can just make their monthly rent and keep the kids in shoes. A $30,000 Prius or a $40,000 Volt isn't going to fit into the monthly budget of most folks unless we want to turn a sizable portion of the population into debt slaves more than they already are.

This great country has the brains and resources to solve our energy issues. But it has to start with an honest and open debate that is centered around science. And, we have to find some consensus about what goal it is we are trying to achieve. Is it energy independence? Is it low CO2 emissions? Is it maintaining our standard of living and personal mobility? Any and everything is possible, but there will be trade-offs that need to be understood before we head down any more dead ends.

[chester8420]

I dug up this old post looking for info on E-85, and I got really upset reading it. There are a lot of comments from people who have no clue about corn farmers the corn market, and what it means to our economy.

E-85 is one of the best things to happen to the automotive industry in years IMO. I'm fed up with giving Iraq oil money. Our boys are over there dying everyday, and we're supporting them with billions in oil money a year.

E-85 is an alternative fuel that requires minor or no changes to any gasoline engine to run. And all the cash stays in this country! Sure there's better ways, and they will come. But this is now.

I'm not trying to start a debate, but I just wanted to give the other side of the story that you never hear. And I AM a corn farmer. We sell 95% of our corn to Tyson (chicken feed). They are a very good company to do business with too!