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      07-23-2013, 06:10 PM   #1
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Question Negative effects of using Ethanol blends?

So I have read/seen a lot of people talking about using E85 blends, (E30 etc), and getting HUGE power gains out of it when tuned correctly.

Why have I not really seen ANYTHING/or ANYBODY talk about the negative effects of using it?

For example, these fuel pumps are going bad for many reasons, but American's using Ethanol in our normal gas being a root cause (true or not I am not sure).

Or I've heard diesel mechanics discuss ethanol frying piston rings on gasoline motors,
OR
Damaging the entire fuel system because ethanol is naturally corrosive.

Since the system is not designed to run E85, there has to be significant negative impacts on the motors/fuel system that can not be corrected by different fuel mapping? Or am I just plain wrong?

I live in Colorado where E85 is readily available, and I could use all the help I could get at this altitude.

Any input from experts?

Thanks!
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      07-23-2013, 06:13 PM   #2
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Unfortunately there really isn't a lot of hard data around long term use of Ethanol. Other platforms have been using E85 for a long time without issues (EVO guys), but nothing for our platform, but I have been running 100% E85 or about the last 4-5k miles without issues. I guess I am just taking my chances But it's one of those things where you need to do your own research and determine if the risk is worth it to you.
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      07-23-2013, 06:17 PM   #3
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Quote:
Originally Posted by I6+TT=FTW
So I have read/seen a lot of people talking about using E85 blends, (E30 etc), and getting HUGE power gains out of it when tuned correctly.

Why have I not really seen ANYTHING/or ANYBODY talk about the negative effects of using it?

For example, these fuel pumps are going bad for many reasons, but American's using Ethanol in our normal gas being a root cause (true or not I am not sure).

Or I've heard diesel mechanics discuss ethanol frying piston rings on gasoline motors,
OR
Damaging the entire fuel system because ethanol is naturally corrosive.

Since the system is not designed to run E85, there has to be significant negative impacts on the motors/fuel system that can not be corrected by different fuel mapping? Or am I just plain wrong?

I live in Colorado where E85 is readily available, and I could use all the help I could get at this altitude.

Any input from experts?

Thanks!
So far the one problem I've seen when running e85 on this platform is that overtime the injectors will get clogged up with a sticky brown almost caramel like substance. When this happens, I usually go about cleaning them by running 2 tanks of straight chevron 91 pump gas with techron, and resetting the adaptations. I then run e85 again, and the problems I was experiencing are gone. I can't speak for longevity of the engine, or the fuel system components, but what I have heard for the most part are that the lines are able to handle ethanol on newer cars due to the amount of ethanol being mixed in pump gas nowadays. I'm not stating this as fact, just a notion I'm going off of based on what I've heard and read from this community.
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      07-23-2013, 06:23 PM   #4
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Quote:
Originally Posted by I6+TT=FTW View Post
So I have read/seen a lot of people talking about using E85 blends, (E30 etc), and getting HUGE power gains out of it when tuned correctly.

Why have I not really seen ANYTHING/or ANYBODY talk about the negative effects of using it?

For example, these fuel pumps are going bad for many reasons, but American's using Ethanol in our normal gas being a root cause (true or not I am not sure).

Or I've heard diesel mechanics discuss ethanol frying piston rings on gasoline motors,
OR
Damaging the entire fuel system because ethanol is naturally corrosive.

Since the system is not designed to run E85, there has to be significant negative impacts on the motors/fuel system that can not be corrected by different fuel mapping? Or am I just plain wrong?

I live in Colorado where E85 is readily available, and I could use all the help I could get at this altitude.

Any input from experts?

Thanks!
This is a hard question to answer. We have companies saying that it does harm to the car but not much proof otherwise since there are not many cars running full e85.

I know there are many evo's supra's ect... that run them. Maybe you'll get a better awnser on this in a their forum? Then again people probably blow up there engine before ethenol even has a chance to mess it up naturally

In the usa, 10% ethanol has been in the cars since the 80s. When car manufactures manufacture parts they make coatings to protect against ethanol. Normally companies always aim for much higher standards than the required standards so if they are trying to protect against ethanol they are probably building parts that will protect against it 90% of the time. I cant be 100% on this and im sure others might chime in on it as well, but when it comes to car manufactures tend to make things better than standard to help against wear.

The only way to truly know is to be a ginny pig and see what happens after 10 years. As long as your tuned for you'll be fine running it, longevity wise is a question. From what i've been reading on these forums I get the feeling that the 335i bmw's tunes are very adaptive especially with an aftermarket tune.

If you were to compare apples to apples say running Race gas all day every day, you would spend a fortune doing so. The amount of money you would save running ethanol would pay for its self in repairs to parts that might get affected by it after a little while. So if you like the idea of having a "race" gas on demand then ethenal wouldn't be such a big deal. Like any car, parts fail in this instance you might have a few more things that go like seals, or injectors ect...

I've also been reading that bmw created new injectors that work much better than our current ones. I bet those will be much better with ethanol.

Running ethanol is also good for your engine since it lowers pings. In a hot environment you will have more of a reason to use it (especially on CA 91 gas) since it'll make your run alot better.
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      07-23-2013, 06:30 PM   #5
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Originally Posted by Dmacc View Post
So far the one problem I've seen when running e85 on this platform is that overtime the injectors will get clogged up with a sticky brown almost caramel like substance. When this happens, I usually go about cleaning them by running 2 tanks of straight chevron 91 pump gas with techron, and resetting the adaptations. I then run e85 again, and the problems I was experiencing are gone. I can't speak for longevity of the engine, or the fuel system components, but what I have heard for the most part are that the lines are able to handle ethanol on newer cars due to the amount of ethanol being mixed in pump gas nowadays. I'm not stating this as fact, just a notion I'm going off of based on what I've heard and read from this community.
how often would you say you run chevron 91 + techron to clean up the injectors? also, do you have any pics of the clogged injectors? or link to such pics?

thanks in advance
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      07-23-2013, 06:38 PM   #6
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Quote:
Originally Posted by I6+TT=FTW View Post
So I have read/seen a lot of people talking about using E85 blends, (E30 etc), and getting HUGE power gains out of it when tuned correctly.

Why have I not really seen ANYTHING/or ANYBODY talk about the negative effects of using it?

For example, these fuel pumps are going bad for many reasons, but American's using Ethanol in our normal gas being a root cause (true or not I am not sure).

Or I've heard diesel mechanics discuss ethanol frying piston rings on gasoline motors,
OR
Damaging the entire fuel system because ethanol is naturally corrosive.

Since the system is not designed to run E85, there has to be significant negative impacts on the motors/fuel system that can not be corrected by different fuel mapping? Or am I just plain wrong?

I live in Colorado where E85 is readily available, and I could use all the help I could get at this altitude.

Any input from experts?

Thanks!
While these cars weren't designed to run E85, there is ~10% ethanol in most pump gas you buy these days and the fuel systems are built to handle it. The rumor I hear is that E15 might become the new standard soon. Either way, I have no worries at all running 30% ethanol in my car on every tank.

The problem with the high pressure fuel pumps was more a manufacturing issue than anything. BMW provided the design details for the pumps and an outside manufacturer built them. Problem was that the N54 equipped vehicles sold far better than BMW expected. Pump production was cranked up and quality suffered. A long, drawn out lawsuit followed, with BMW trying to break their contract with the supplier before they actually succeeded. This actually happened with 2 suppliers in other countries before BMW moved pump production to Germany where it could be closely watched for quality control. The new pumps are reliable in my opinion.

Back on topic....
E85 isn't going to "fry piston rings" or anything of the sort if tuned properly. It has a much different stoich value than gasoline, so DME map changes are a must to prevent the engine from running lean. It also puts more load on the fuel system for this reason (more E85 volume is required vs. gasoline). Again, you could run the engine lean if you aren't careful. If you are aware of what you're doing with your car, I don't see any real downside to running more ethanol. Besides the extra effort of mixing and a small loss of MPG, that is.
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      07-23-2013, 06:45 PM   #7
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Quote:
Originally Posted by BMWM.D. View Post
While these cars weren't designed to run E85, there is ~10% ethanol in most pump gas you buy these days and the fuel systems are built to handle it. The rumor I hear is that E15 might become the new standard soon. Either way, I have no worries at all running 30% ethanol in my car on every tank.

The problem with the high pressure fuel pumps was more a manufacturing issue than anything. BMW provided the design details for the pumps and an outside manufacturer built them. Problem was that the N54 equipped vehicles sold far better than BMW expected. Pump production was cranked up and quality suffered. A long, drawn out lawsuit followed, with BMW trying to break their contract with the supplier before they actually succeeded. This actually happened with 2 suppliers in other countries before BMW moved pump production to Germany where it could be closely watched for quality control. The new pumps are reliable in my opinion.

Back on topic....
E85 isn't going to "fry piston rings" or anything of the sort if tuned properly. It has a much different stoich value than gasoline, so DME map changes are a must to prevent the engine from running lean. It also puts more load on the fuel system for this reason (more E85 volume is required vs. gasoline). Again, you could run the engine lean if you aren't careful. If you are aware of what you're doing with your car, I don't see any real downside to running more ethanol. Besides the extra effort of mixing and a small loss of MPG, that is.
Very well put.
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      07-23-2013, 06:49 PM   #8
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I think BMWM.D puts it best. That combined with the ever-increasing amount of ethanol blends in the gasoline (as well as the 25% in Brazil) means that most fueling systems are designed to, chemically, handle the ethanol. The only concern after that are making sure the system is tuned for higher fuel flow. (about 30% more fuel flow for any given load?) I have been running ethanol in my tank for a year with no hardware issues that can be specifically attributed to ethanol problems. Right now, it has been about 8-10000 miles running with considerable amounts of ethanol in the tank (varying from 40% to 80%) My only problems right now are software-related (rough cold start idle and codes thrown on sustained partial boost).

An additional question: If your car is making 60% more horsepower, and ethanol is 30% more per horsepower, then is it 1.6*1.3 = fuel pump is working twice as hard?
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      07-23-2013, 07:16 PM   #9
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Quote:
Originally Posted by phazedkid
Quote:
Originally Posted by Dmacc View Post
So far the one problem I've seen when running e85 on this platform is that overtime the injectors will get clogged up with a sticky brown almost caramel like substance. When this happens, I usually go about cleaning them by running 2 tanks of straight chevron 91 pump gas with techron, and resetting the adaptations. I then run e85 again, and the problems I was experiencing are gone. I can't speak for longevity of the engine, or the fuel system components, but what I have heard for the most part are that the lines are able to handle ethanol on newer cars due to the amount of ethanol being mixed in pump gas nowadays. I'm not stating this as fact, just a notion I'm going off of based on what I've heard and read from this community.
how often would you say you run chevron 91 + techron to clean up the injectors? also, do you have any pics of the clogged injectors? or link to such pics?

thanks in advance
I'm on the mobile app right now but I'll see if I can find the thread I saw with pictures of the gooey substance, I usually run 4-5 tanks of straight e85 before I start to see the issue, the reason I run more than one tank in a row of pump gas to clean it up is to ensure that the techron is doing its job and that there is no e85 in the tank when doing so. Just a precaution that I take. JoeC also posted a while ago in a thread of some flex fuel system cleaner he uses every now and then to clear them up, I believe fftec recommends it, I'll see if I can pull that up when I get home.
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      07-23-2013, 07:19 PM   #10
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These are the kind of answers I have been looking for! Except for the lack of hard data (due to time limitations on this platform). i know people with EVOs have been running E85 for awhile now, but with upgrade walbro fuel pumps (most of the time I think).
Thanks BMWM.D and everyone else.
Anyone else been running ethanol for AWHILE now that might be able to chime in?
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      07-23-2013, 07:45 PM   #11
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Quote:
Originally Posted by Dmacc View Post
I'm on the mobile app right now but I'll see if I can find the thread I saw with pictures of the gooey substance, I usually run 4-5 tanks of straight e85 before I start to see the issue, the reason I run more than one tank in a row of pump gas to clean it up is to ensure that the techron is doing its job and that there is no e85 in the tank when doing so. Just a precaution that I take. JoeC also posted a while ago in a thread of some flex fuel system cleaner he uses every now and then to clear them up, I believe fftec recommends it, I'll see if I can pull that up when I get home.
Yah I buy the stuff at Walmart, I will check my trunk as I keep bottles of it back there. But it comes in a little green bottle.

Also that brown gunk is probably the sugars in the Ethanol. My guess is that it's going through a caramelizing process like when you put sugar on a frying pan.
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      07-23-2013, 08:35 PM   #12
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Unfortunately there really isn't a lot of hard data around long term use of Ethanol. Other platforms have been using E85 for a long time without issues (EVO guys), but nothing for our platform, but I have been running 100% E85 or about the last 4-5k miles without issues. I guess I am just taking my chances But it's one of those things where you need to do your own research and determine if the risk is worth it to you.
Second everything he said - mileage using 100% e85, no issues, weigh the risks....
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      07-23-2013, 09:47 PM   #13
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I'm on the mobile app right now but I'll see if I can find the thread I saw with pictures of the gooey substance, I usually run 4-5 tanks of straight e85 before I start to see the issue, the reason I run more than one tank in a row of pump gas to clean it up is to ensure that the techron is doing its job and that there is no e85 in the tank when doing so. Just a precaution that I take. JoeC also posted a while ago in a thread of some flex fuel system cleaner he uses every now and then to clear them up, I believe fftec recommends it, I'll see if I can pull that up when I get home.
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Originally Posted by joec500 View Post
Yah I buy the stuff at Walmart, I will check my trunk as I keep bottles of it back there. But it comes in a little green bottle.

Also that brown gunk is probably the sugars in the Ethanol. My guess is that it's going through a caramelizing process like when you put sugar on a frying pan.
Got ya. If you get a chance, let me know exactly what cleaner you run, JoeC. Just joined the e85 game and trying to stay informed. Thanks guys.
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      07-23-2013, 10:16 PM   #14
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Originally Posted by BMWM.D. View Post

E85 isn't going to "fry piston rings" or anything of the sort if tuned properly. It has a much different stoich value than gasoline, so DME map changes are a must to prevent the engine from running lean. It also puts more load on the fuel system for this reason (more E85 volume is required vs. gasoline). Again, you could run the engine lean if you aren't careful.
I must be missing something........because when you look at the logs the tuners make for running E85, they actually lean out the AFR to around 14:1.

Isn't stoich for E85 around 9:1?

Much richer than the AFR for gasoline.

So why are they leaning out the AFR to be higher than when tuned for pump gas at around 12:1....
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      07-23-2013, 10:20 PM   #15
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Also found this on Wiki: http://en.wikipedia.org/wiki/E85



E85 ethanol is used in engines modified to accept higher concentrations of ethanol. Such flexible-fuel vehicles (FFV) are designed to run on any mixture of gasoline or ethanol with up to 85% ethanol by volume. There are a few major differences between FFVs and non-FFVs. One is the elimination of bare magnesium, aluminum, and rubber parts in the fuel system. Another is that fuel pumps must be capable of operating with electrically conductive ethanol instead of non-conducting dielectric gasoline fuel. Fuel-injection control systems have a wider range of pulse widths to inject approximately 34% more fuel. Stainless steel fuel lines, sometimes lined with plastic, and stainless-steel fuel tanks in place of terne fuel tanks are used. In some cases, FFVs use acid-neutralizing motor oil. For vehicles with fuel-tank-mounted fuel pumps, additional differences to prevent arcing, as well as flame arrestors positioned in the tank's fill pipe, are also sometimes used.
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      07-23-2013, 10:30 PM   #16
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Also found this on Wiki: http://en.wikipedia.org/wiki/E85



E85 ethanol is used in engines modified to accept higher concentrations of ethanol. Such flexible-fuel vehicles (FFV) are designed to run on any mixture of gasoline or ethanol with up to 85% ethanol by volume. There are a few major differences between FFVs and non-FFVs. One is the elimination of bare magnesium, aluminum, and rubber parts in the fuel system. Another is that fuel pumps must be capable of operating with electrically conductive ethanol instead of non-conducting dielectric gasoline fuel. Fuel-injection control systems have a wider range of pulse widths to inject approximately 34% more fuel. Stainless steel fuel lines, sometimes lined with plastic, and stainless-steel fuel tanks in place of terne fuel tanks are used. In some cases, FFVs use acid-neutralizing motor oil. For vehicles with fuel-tank-mounted fuel pumps, additional differences to prevent arcing, as well as flame arrestors positioned in the tank's fill pipe, are also sometimes used.
That's the stuff I have been thinking about!
Increasing fuel by 30% is fine, no biggie.
But what about the tank, pumps, seals, fuel lines, changing oil type or just increase change intervals, injectors (apparently sugar build up, fixed by techron treatment(s)), etc etc?
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      07-23-2013, 10:35 PM   #17
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Quote:
Originally Posted by Ilma
Quote:
Originally Posted by BMWM.D. View Post

E85 isn't going to "fry piston rings" or anything of the sort if tuned properly. It has a much different stoich value than gasoline, so DME map changes are a must to prevent the engine from running lean. It also puts more load on the fuel system for this reason (more E85 volume is required vs. gasoline). Again, you could run the engine lean if you aren't careful.
I must be missing something........because when you look at the logs the tuners make for running E85, they actually lean out the AFR to around 14:1.

Isn't stoich for E85 around 9:1?

Much richer than the AFR for gasoline.

So why are they leaning out the AFR to be higher than when tuned for pump gas at around 12:1....
Ethanol burns at a much cooler temperature than gasoline, and also has a higher equivalent octane rating, that's why you are able to lean it out more, because of its in cylinder cooling effects, as far as I understand.
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      07-23-2013, 10:48 PM   #18
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Ethanol burns at a much cooler temperature than gasoline, and also has a higher equivalent octane rating, that's why you are able to lean it out more, because of its in cylinder cooling effects, as far as I understand.
So the tuners are not tuning for Ethanols's stoich of 9:1 then.

Sounds like they are leaning out the pump gas AFR to get maximum power and relying on the cooling benefits of ethanol to supress any detonation.

Makes some sense at 30% E85 blends or so......but as you increase the amount of E85 I would think the lambda ratio would alter.

Aren't the O2 sensors in our cars based on a lambda of around 1?

In otherwords, they alter the amount of fuel until all the oxygen is effectively burned.

As you increase the % of ethanol in your mix, wouldn't you need less oxygen to achieve lambda since ethanol runs richer.

I don't think the O2 sensors know you are running E85......they just measure the amount of residual oxygen in your exhaust fumes.
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      07-23-2013, 10:51 PM   #19
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Thinking something like this then:

The best ratio for gas mixture is 14.7 parts air to 1 part fuel.
The best ratio for e85 mixture is 9.8 parts air to 1 part fuel.

The O2 sensor does not know how much air or fuel you started with. It only knows oxygen levels left in the spent exhaust.

The O2 sensor reports in terms of lambda. If the lambda value is 1.0, the fuel is burned optimally, and started with the right mix. Whether you start with gas at 14.7:1 or e85 at 9.8:1, the lambda will be the same at the O2 sensor.

So are the datalogs reporting the gasoline equivalent AFR while using E85.

Since gasoline stoich is 14:1 this means that the O2 sensor is returning a lambda of 1 (all oxygen burned) but you are probably really running a richer AFR for E85 than what is showing.

In the end, a lambda of 1 would simply mean you are burning the all the oxygen that is required by the E85 blend in the tank.......but the more ethanol you run, I would guess that lambda gets closer to the 9:1 stoich that ethanol needs in order to burn all the oxygen molecules in the AFR.
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      07-23-2013, 11:33 PM   #20
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Stock DME in both 335 and m3 are target based closed loop only. I have logged data running 30 percent Ethanol and afr is perfect as car adapts by targeting lambda as mentioned.

Car will read a "lean" condition for a millisecond and then start pumping out more and more fuel (30 percent more roughtly if running e30) and it will even out the AFR very quickly.
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      07-23-2013, 11:38 PM   #21
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Negatives:

Harder working fuel pumps
Worse fuel economy (e85 has less energy density)
Could affect rubber seals
Turns to corn syrup (ask anyone with a carb'd motorcycle that's sat for a while)

For many people, the higher octane and boost are worth the tradeoffs.
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      07-23-2013, 11:46 PM   #22
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Originally Posted by Ilma View Post
Thinking something like this then:

The best ratio for gas mixture is 14.7 parts air to 1 part fuel.
The best ratio for e85 mixture is 9.8 parts air to 1 part fuel.

The O2 sensor does not know how much air or fuel you started with. It only knows oxygen levels left in the spent exhaust.

The O2 sensor reports in terms of lambda. If the lambda value is 1.0, the fuel is burned optimally, and started with the right mix. Whether you start with gas at 14.7:1 or e85 at 9.8:1, the lambda will be the same at the O2 sensor.

So are the datalogs reporting the gasoline equivalent AFR while using E85.

Since gasoline stoich is 14:1 this means that the O2 sensor is returning a lambda of 1 (all oxygen burned) but you are probably really running a richer AFR for E85 than what is showing.

In the end, a lambda of 1 would simply mean you are burning the all the oxygen that is required by the E85 blend in the tank.......but the more ethanol you run, I would guess that lambda gets closer to the 9:1 stoich that ethanol needs in order to burn all the oxygen molecules in the AFR.
Correct.
Lambda is what matters. It is just interpreted as "respective gas AFR" in the logs for consistency and convenience if you think positively The "true AFR" doesn't really matter.

Closed loop reads lambdas and adjust them automatically so that we don't need to bother about different AFRs of different fuels.

Last edited by jippii ensio; 07-24-2013 at 12:14 AM.
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