Drop in gas mileage, Ethanol?

[falcon556]

mileage also drops with colder temps, engines are running rich longer, to warm up, grease and oil is thicker, giving greater friction during warm up

I was trying to make a comparison of 2WD vs 4x4 FT gas mileage. I would zero my odometer every single time I bought gas and then right down the miles/gallons.
With my mixed HWY/City driving it was amazingly constant till the end of summer. Suddenly it dropped. At first I attributed it to traffic, driving habits, quick starts etc. After a while it was obvious that something else happened. Quite frankly I thought my O2 sensor went bad and I was planning to do something about it.
Quiktrip said that they switched at the end of the summer.
Same time my mileage dropped.

 

[w_howey]

Under benefits I see a lot of political correctness and BS, nothing that will benefit me or my Jeep.
I called around and Shell and Phillips 66 supposedly still use ethanol free gas.
I hope they stay that way.

In OK, with the large oil economy you have there, you might not see the complete conversion quickly, but you will....

I travel for work too much, I was in California during the MTBE affair. There were brochures, posters and etc. at RDP/Shell and Exxon/Mobil stations blasting ethanol vs. MTBE. In Illinois, Iowa, etc. The posters, brochures, etc. were all blasting MTBE vs. ethanol, these were still RDP/Shell and Exxon/Mobil stations.

Politics is a huge component of this, and nothing will change that. I don't know the exact breakdown of the EPA rulings now, but as the number of residents and enviromental impact of those people rise you will see additional stations switch first to e10 fuel in the winter and eventually year round. The 'winter blend' fuels stations sell now are going to be ethanol blended.

 

[falcon556]

The 'winter blend' fuels stations sell now are going to be ethanol blended.

I called Shell and they said they are ethanol free. Unfortunately it was New Years eve and a lot of people had left early, I don't think I talked to the right person.

BTW all that time that I was driving in 2WD or 4x4 FT and checked my mileage, I didn't notice any difference in mileage, which was the reason behind my testing.

 

[lawsoncl]

http://www.fullflexint.com/pages/vehicles.htm#Chrysler_&_Jeep

http://www.flextek.com/shop.htm

there ya go...

It looks like the FlexTek kit goes in between the PCM and the injectors? Is it just keeping them on longer on each pulse? It would make more sense just to bump up the fuel rail pressure so they flow more. Either way, I won't how you handle switching back-n-forth between the fuels. I labelled them as snake oil as soon as I saw the "fuel system conditioner" and the special motor oil they recommend.

 

[RichP]

One of the posters here from Brazil runs E85 BUT he also had his engine built to higher compression. E85 actually works well in an engine with an 11:1 or better compression ratio. When this came up about 2 years ago he said he was getting close to 26mpg on the alcohol. Also US manufacturers who build cars for export to south america build high compression engines just for export. The downside is that you can't run it on regular once you go above about 9.5:1 or 10:1.
Alcohol fueled funny cars are an example, they run well and fast and have been for many many years.

 

[Ecomike]

So does that mean the ethanol they are adding is free?????:laugh3:

I was under the impression the 10% ethanol was now nationwide, universal in the USA, but there may be isolated pockets of areas not using it yet. It is mandatory in some (if not all now) parts of the country now to meet EPA volatility and oxygenation requirements for the fuel. But some gas stations may still be getting the old stuff until they have had the chance (there is a deadline I think) to modify there equipment. I don't know the exact details, but the switch from MTBE to ethanol as the Oxygenation additive in the gas requires some tank, pump, or metering equipment upgrades, as well as tank flushing I think, before they switch over the gas station to E10 ethanol. I think there was also a reduction in the sulfur content of the gasoline this year as well, I know there was for the diesel, it may have been last year that the gas lost most of its remianing sulfur.

I called Shell and they said they are ethanol free. Unfortunately it was New Years eve and a lot of people had left early, I don't think I talked to the right person.

BTW all that time that I was driving in 2WD or 4x4 FT and checked my mileage, I didn't notice any difference in mileage, which was the reason behind my testing.

 

[RichP]

So does that mean the ethanol they are adding is free?????:laugh3:

I was under the impression the 10% ethanol was now nationwide, universal in the USA, but there may be isolated pockets of areas not using it yet. It is mandatory in some (if not all now) parts of the country now to meet EPA volatility and oxygenation requirements for the fuel. But some gas stations may still be getting the old stuff until they have had the chance (there is a deadline I think) to modify there equipment. I don't know the exact details, but the switch from MTBE to ethanol as the Oxygenation additive in the gas requires some tank, pump, or metering equipment upgrades, as well as tank flushing I think, before they switch over the gas station to E10 ethanol. I think there was also a reduction in the sulfur content of the gasoline this year as well, I know there was for the diesel, it may have been last year that the gas lost most of its remianing sulfur.

I think or seem to remember that ethanol was a replacment for the MTB stuff that went in winter fuel, I know here that E10 vanishes in the spring, summer and fall and is only winter gase here in Pa and NJ.

 

[lawsoncl]

EPA is only mandating a certain amount of ethanol be used as an oxygenate, which for 2007 came up to about 4% of the gasoline sold. The new requirement for 2008 with projected gasoline sales will put that percentage at 4.7%. These totals are easily met using 10% mix in the winter and the E85 sales. EPA is mandating the phase out of MBTE due to studies showing its finding it's way into ground water and also limits ethanol to 10% in "normal" gas. The states have their own say and a few have mandated the gas be diluted 10% year round. California wants to push for even higher percentages, regardless of the fact that 95% of the cars on the road can not run with more than 10% ethanol.

 

[lawsoncl]

One of the posters here from Brazil runs E85 BUT he also had his engine built to higher compression. E85 actually works well in an engine with an 11:1 or better compression ratio. When this came up about 2 years ago he said he was getting close to 26mpg on the alcohol. Also US manufacturers who build cars for export to south america build high compression engines just for export. The downside is that you can't run it on regular once you go above about 9.5:1 or 10:1.
Alcohol fueled funny cars are an example, they run well and fast and have been for many many years.

And that's a major catch-22 with E85. If you modify the engine to run really well on E85, it can't run regular gas. Nobody is going to buy a car that won't run on normal gas because E85 is not widely available yet. The auto makers are getting their credits (about 1.5mpg CAFE credits) just for making flex fuel vehicles. The don't actually care if people put E85 in them or whether they run well on it.

I'm banking on butanol. It's a drop in replacement for gas, but it's currently too expensive to mass produce. There is some promising research using alge and bacteria to produce it in quantities. It can use the existing pipeline infrastructure and distribution system (ethanol and E85 can't) and runs just fine in non-flex fuel vehicles with comparable gas mileage. It also burns much cleaner than gas.

 

[Ecomike]

EPA is only mandating a certain amount of ethanol be used as an oxygenate, which for 2007 came up to about 4% of the gasoline sold. The new requirement for 2008 with projected gasoline sales will put that percentage at 4.7%. These totals are easily met using 10% mix in the winter and the E85 sales. EPA is mandating the phase out of MBTE due to studies showing its finding it's way into ground water and also limits ethanol to 10% in "normal" gas. The states have their own say and a few have mandated the gas be diluted 10% year round. California wants to push for even higher percentages, regardless of the fact that 95% of the cars on the road can not run with more than 10% ethanol.

IIRC, here in Texas, the TCEQ (Texas EPA) has mandated the 10% ethanol in the summer months in non-attainment (8/24 hour ozone requirement) counties to lower the volatility in the hot summer months as part of the Texas plan to meet EPA ozone limits, and thus maintain the flow federal highway funds to Texas in places like Houston and Dallas. For some other reason I got the impression we are just now using it year round, but I could be mistaken. I thought there was also a push to go to E10 year round nation wide to reduce oil imports after Bush's last state of the union message. It seems to be a moving target lately.

 

[Ecomike]

I should probably be answering this question myself, but it just dawned on me! Let's see, the E-10 has more oxygen in it already, partly oxidized if you will, it burns differently, cooler and slower(?), it's density is different (don't know how much off the top of my head but)..................so is the 14.7:1 ratio that our O2 sensors are tuned for the best A/F ratio for E-10?

 

[lawsoncl]

Oxygen sensors are tuned to have a sweet spot at a certain percentage of O2 in the exhaust. It doesn't know about the a/f ratio that went into producing the exhaust. The engine computer is the one that needs to figure that out, and you are correct in assuming that the a/f ratio will be different. One of the reasons for putting ethanol in was to lean out the older carbed vehicles that couldn't dynamically adapt their a/f ratio. Ethanol requires more air per gallon of fuel to properly burn.

 

[RichP]

Oxygen sensors are tuned to have a sweet spot at a certain percentage of O2 in the exhaust. It doesn't know about the a/f ratio that went into producing the exhaust. The engine computer is the one that needs to figure that out, and you are correct in assuming that the a/f ratio will be different. One of the reasons for putting ethanol in was to lean out the older carbed vehicles that couldn't dynamically adapt their a/f ratio. Ethanol requires more air per gallon of fuel to properly burn.

I don't think more air, I think more pressure, compression, makes it burn properly more efficiently.

 

[Ecomike]

I don't think more air, I think more pressure, compression, makes it burn properly more efficiently.

That can get kind of tricky since ethanol is polar and thus I think denser than octane, or the original gasoline, on a molar basis I would agree that ethanol would need less air than gasoline (with out additives like ethanol), but on a volume of air (gas) to volume of liquid ethanol basis, it might take more air if the liquid fuel density difference is large enough. ???

Certainly an interesting topic!!!! The ethanol is less flamable, lower flash point, like diesel, yes (?), and thus can take advantage of higher compression ratio efficiencies than gasoline can handle without detination, yes????

Anyway it sounds like an opportunity for retuning the computers and O2 sensors for E-10, ????

 

[kujito]

If your gas station is selling you E10, then there is a sticker on the pump telling you so. The stickers are about 1.5" by 1.5" and printed in black and white. If the station's tanks have been filled with E10, the stickers must legally be on the pump.
EPA can mandate that a metro area HAS to use it if the area has not scored well on the EPA's pollution scale over a given period of time (can't remember exact numbers/timeframes). Like Ecomike has seen in TX, Denver usually switches to the stuff for summer as well.

 

[falcon556]

If your gas station is selling you E10, then there is a sticker on the pump telling you so. The stickers are about 1.5" by 1.5" and printed in black and white. If the station's tanks have been filled with E10, the stickers must legally be on the pump.

Not in my area, the vast majority sell E10 and people think they are buying gas.

 

[LittleRedXJ]

Not in my area, the vast majority sell E10 and people think they are buying gas.

Yeah, in NH I've noticed some places with stickers on the pumps and some without. The ethanol killed two fuel filters in a row on our Jetta in the summer of '06.

 

[crystalship1]

Hit or miss labeling here in Indiana. :doh:


BTW - This thread IS from January.

:cheers: