Will using gasoline with added ethanol have any bad effects on a VQ35? In my part of the state (southwest VA) no one adds ethanol that I know of. I'm over in Norfolk and had to fill up and several places had 10% ethanol fuel.

 

I belive up north here, they all add it during the cold months, and some may add it all year some may not. I dont like the stuff, it hurts your MPG and its not the best thing ever for injectors. However, is it bad? Nah, if you can get gas without it try to (as i said this part of the year that may not be possible) but its not really bad, just not as good as regular old gas.

If i were you i would throw a bottle of good injector cleaner in there every so often to help with it (Chevron Techron, Gunmont Regane, or Fuelpower (google lubecontrol for that one) are the only real good cleaners)


Anyway, hope that helps

 

Thanks for the reply. I do use the Techron every 2 oil changes.

Why do they add it to gasoline anyway? Why does it hurt the mpg?

 

I use 10% ethanol gasoline all the time. Where I'm from users get better results in their emissions tests. It also suspends any moisture in the fuel system and spits it out, so it is good to use in the winter and will also prevent gasline freezing.

Based on my experience, the notion that you get lower fuel economy is BS and although I defer to the wisdom of kcryan, I don't agree with the theory of fouling the fuel injectors.

It may be, however, that the 10% ethanol-blend gasoline I use is different that what is used in the United States.

Long story short, my fuel economy hasn't been compromised one iota. I still get better fuel economy than 99% of the .orgers and I am still running the OEM plugs with 64K, mostly highway miles on them.

My fuel economy experience may have something to do with gas in Canada being better than the crap sold in the United States.

 

If you aren't seeing a decrease in gas mileage using 10% enthanol-blend gas, then your O2 sensors aren't working properly.

Oxygen is a by-product of combustion of ethanol. When your O2 sensors see oxygen in the exhaust, they'll interpret that as you running lean and richen up your air/fuel mixture, which will obviously decrease your gas mileage. Ethanol also has less energy than gasoline so you will see a slight decrease in power using 10% blend as well.

Both of the above are fairly "minimal" in their impact, but they are more fact than Bobo's fuel economy observations.

I, personally, avoid 10% ethanol-blended gas when possible as I HAVE noticed a decrease in fuel economy. However, with that said, I don't believe it will do any kind of damage and I don't hesitate to put it into my car if it's more convenient.

 

ethanol has about 45% less energy than straight gas. mixed in at 10% the effect on mpg is negligible (this is b/c an ICE does not extract all available energy from fuel to begin with). studies I've seen say about 1.5% mpg hit, which will get lost in the "noise floor" of variables that affect mpg calculations from tank to tank. the cumulative effect over millions of cars, however, is substantial. and I question the net environmental gain E10 fuels offer over gasoline. politically, I would love to see us running E85 in every car, giving OPEC the big finger, and channeling wealth back into the great plains farmlands.

damage to engines is debatable. my personal belief - based on doing dozens of tune-ups on cars from both the RFG midwest and parts of arizona and nevada that (until recently) still used conventional gasoline - is that E10 does cause more deposits than straight gas. climate/temperature, driving conditions, etc also play a role, but I'd like to believe it has more to do with crappy gas.

anecdotally, many people I've talked to who have used both E10 and straight gas will swear their cars run better on the gas. I have no reason to doubt that.

 

The primary reason I use the ethanol-based gasoline is that the company that markets it locally sells 90-octane ethanol at the price of 87 everywhere else. The incremental cost of using 89 or 91 octane elsewhere is 6 and 11.5 cents per litre, respectively. We also have 92 and 94 octane at a few stations, but there is no such thing as 93 octane.

My car seems to run better on the 90-octane ethanol gas than any 89 octane gas.

 

Hey guys,
Got intersted i this thread so here it is. I run my maxima and have a 68 camaro thats done up hard. I live in Mass and when they started t oput the ethenol in there was a very noticable difference in MPG and performance. he maxima went down by 2-3 mpgs and the cam lost about 1/10- 2/10 in the 1/4. Funny you guys are talking aobut this as there is a write up in the Feb issue of Chevy hi performance.
Here is a link to a site that is basically what the article states. And yes from the whs who of gas they state it does drop MPG and also he states

"the drawbacks of using ethenol in gas is that the final mixture can loosen debris in your vehicles gas tank- therefor plugging the filter-and can attack and deterioate the soft parts of a fuel system. Likewise it has less energy that straight gasoline, which reduces fule economy slightly, and it artificially increases the vapor pressure of the gasoline, making it more difficult to blend a product that is free from vaporlock."

http://www.idavette.net/hib/fuel/index.htm
http://www.aera.org/docs/shopt/shptlk-1205.pdf
http://www.hotrod.com/techarticles/f...son/index.html

 

There is a definite difference running E10 Vs. 100% gasoline. I've made several trips to Southern states with my Maxima and EVERYTIME I get some real gasoline my fuel economy goes up. I usually achieve 26~28 MPG on all highway trips with E10, with pure gas I have seen fuel economy as great as 33 MPG highway and averaging 30~31 MPG usually. I always travel at night with little to no traffic and most of the time I keep it at 75 MPH using the cruise control.

IMO this stuff is garbage it's what happens when the oil companies and politicians come together to screw us. There is a slight decrease in emissons on older cars and motorcycles but we lose fuel economy so we consume more gasoline, what's the point in that? Regardless if it's E10 that's still going to increase the amount of CO2 we put out every year. What's worse is that engines with working o2 sensors see even less of a benefit. Some Mass gas stations used to have E10 I used to avoid it but now every gas station in New England uses it as does NY state.


And Id like to add...



It's a bit blurry but this was heading home from Maxus in 2005. I topped off near Memphis, then drove through Tennesse and got this fuel economy. IIRC it was around 33.6 MPG. That's a range of almost 600 miles per tank.

 

I've read numerous fuel economy threads since I've been a member and this is the highest gas mileage claim I can recall to date.

I don't believe that you can attain 600 miles to a tank cruising at 75 mph.

If you were to state 500 - 550 I could accept it, with closer to 500 being reality at that speed.

I have to call BS on this one!

 

The fuel economy was 33.X MPG. Why do you think I stopped to take a pic? I didn't believe it either. At the next gas fill up I asked the attendent what the hell was in Tenn. gas and they said it's just gasoline no emissons additives. Most of been the Chevron 93 and good clean Tennesse air.

When I left for that trip I topped off in Mass near my home (non ethanol back then) and made it to the outskirts of Buffalo, NY. The low fuel light was on and I had to stop at some shady place to get gas. Then the fuel economy went to hell and I got check engine lights every so often.

So I no longer go all the way to empty. When I pass the middle mark I find a name brand station and top off. From there you can calculate your average fuel economy. Est. range at 33.6 MPG would be around 600 miles. But If I was to goto total empty (all 18 gallons) that would damage the fuel pump. So relax I said a range of about 600 miles not that I drove that far on one tank, that's dangerous.

However my results were not repeatable. I took the same route home from Maxus this year in an attempt to repeat it but only got around 30~31 MPG highway.

 

The biggest E10 problem is storing cars/boats with it, its horrible for that, absoloutly horrible, im worried about my allante with it this winter, but luckily thats only gone for a few months, so i should be ok.

 

I wonder if the ethanol-based gasoline I use is different than in the US.

I believe a lot of the US ethanol is derived from corn, but I believe my ethanol gas is derived from wheat.

I'm not sure if that makes a difference.

 

The most accurate fuel economy estimates are based on a number of tanksful.

However, the accuracy on a single-tank estimate would vastly improve if the vehicle was filled to the brim and then run down until at least the idiot light comes on (and beyond if you can get to a gas station). This is a lot more accurate than partial fillups as the variance in fillups account for erroneously calculated high mpg figures.

I have exceeded 550 miles to a tank about 3 times and 500 miles several times.

 

You don't run to the empty light when your out in the sticks late at night. Especially being a Yankee driving through Tennesse.

I still dont see how it's any different to top off at the half way mark or to top off at the empty mark. The gas burns at an almost linear rate when cruising. The only thing that can effect the results is the gas station ripping you off. That's why I stick with nice looking name brand stations. I've filled it at middle and empty, I can almost tell how much fuel it takes to top it off at each point. Heck you would get better fuel economy the lower you go because of the lighter gas tank.

Regardless if you believe the mileage or not the point was that I've have never gotten decent fuel economy once they switched over to Ethanol. Only crazy fuel economy I get is with southern non-bastardized gasoline.

 

I suppose the mpg calculation might be reasonably accurate if you pump your gas yourself and top it off.

However, gas jockeys could care less and I bet quite often a car would take another gallon of gas after the pump clicks off, but the attendant couldn't be bothered.

 

the single largest source of error (that is, mistakes in the data, not statistical variance) in mpg calculations is the assumption that fill ups always result in the same # gallons in the tank. this error term represents a smaller % error when applied to a full tank of fuel vs. a 1/2 full tank. therefore, running your tank to near empty will yield more accurate mpg calculations. this is a relative comparison, though, and the calculations are still fairly inaccurate even with a full tank. i don't have data to suggest how inaccurate, but i'd guess these "field" mpg calculations have at least +/- 5% error. so differences of less than about 3mpg cannot be considered statistically significant - that is, a 1 or 2 mpg difference is not enough to say a particular type of fuel hurt your fuel economy as that variance could easily be due to erroneous data used in the calculation. mix in the natural variance that arises from wind, speed, temperature, # cold starts, etc and it becomes almost impossible to isolate things that affect fuel economy. city vs. highway driving is really the only thing that stands out from the "statistical noise" and computational error.

 

It's pretty obvious when I can be cruising on these long cross country trips and have 110~130 miles at the 3/4 mark Vs. 150~170 miles from the Southern fuels. This happened to me on both Maxus trips, once I got non-ethanol fuel the economy got better. It also happened traveling to Virginia beach a few weeks ago, on the way home fuel economy was better with the non ethanol Virgina gasoline. It's happened way to many times to be a coincidence.

This is why I don't post what fuel economy I got. I've had that photo for a year and a half now and didn't post it for this reason. Even with photo evidence and over multiple fill ups people still don't believe it.

 

hey 98SE I'm not doubting you. I too get 150+ at the 3/4 mark in the summer on the hwy. and in the winter it falls to about 100. we have oxygenated fuel all year round, though, so fuel can't explain this. in my case it is cold starts, longer idling, and generally running richer due to lower temps. in your case it could be partly due to the fuel, but I'd bet there are other things at play. on these long round trip drives one of the things most people don't realize is that they may be going up more hills one way and down more hills the other. this is certainly true of my trips to northern michigan where I always seem to get better mpg on the way back to Chicago, even though Michigan has RFG year round too. if Michigan had straight gas I'd be tempted to believe it is due to the fuel and not terrain etc. maybe your trips back home from virgina have more down hill driving?? or maybe those southern pumps let more fuel in before they cut off? or maybe the prevailing wind is in one general direction, and is at your back more often on the way home?

anyway my point is that our mpg calculations are little more than broad estimates that can't be taken too literally.

 

sky jumper makes a number of valid points.

Also, assuming an odometer is reasonably accurate, the true test of how far one can go on a tankful of gas is by trying it out.

I have exceeded 550 miles three times, but it certainly wasn't crusing at an average of 75 mph.

To achieve 600 miles on a tank would be admirable, particularly at 75 mph. Given the tach would be reading over 3K, it won't happen.

 

You guys get or have gotten 500 miles from a tank. Is that what the digital readout stated or is that the actual miles driven before the next fill up. Man i ony get about 290 -325. Last winter before we got the E10 it stated i got about 375. So using 93 octane that has e10.. would that attribute for 275 -325 for gas milage now or is a different problem. 500 miles is killer. Even 400 would be sweet.

 

Very good point.....do NOT underestimate the effect of wind on gas mileage. As an **** retentive gas mileage tracker who tries to limit the number of variables that go into my mileage (i.e. same type of gas, same trip repeated, same speed of travel, etc.), I can tell you that the single biggest uncontrollable factor in my gas mileage is the wind speed and direction.

 

As stated I have exceeded 500 miles to a tankful numerous times (probably at least 12) and 550 miles three times. This was based on the trip odometer readings, being full to the brim when leaving and filling to the brim when returning. I have only had two such road trips since using ethanol gas and my fuel economy has been similar to the past, albeit I did an AutoRX trial and switched to synthetic oil at the same time.

In fact, I exceeded 500 miles to a tank last summer, with about 62K on my original OEM platinum plugs.

I can't believe the crappy gas mileage that many .orgers biatch about.

If you ever come to Canada, close your eyes at the pump (the price will make you sick) and fillup with some real gas.

 

This is an interesting post, and one I have a number of opinions about.

- The oil companies don't like having to blend ethanol into gasoline -- for most this is not their idea -- in many parts of the USA it is mandated (can't speak for Canada). Oil companies don't like ethanol because it can not be blended into gasoline at the refinery and then shipped through a pipeline. It must be trucked to each terminal and put in a separate tank. It is then blended with gasoline as it is loaded into trucks that haul the mixture to each gas station. This special blending and special trucking of ethanol raises the cost of each gallon of gasoline. Don't blame the oil companies -- if it weren't mandated, most would not do it, or only do it where corn farmers demanded it.

- Ethanol in gasoline does pick up water in your fuel tank (or anywhere it come in contact with water, which is why it can't be shipped in a pipeline). Before ethanol in gasoline, many would put it in their gas tank in the winter to prevent any water there from freezing (Heet was one popular brand). This is one of the few advantages of ethanol in gasoline.

- Another "advantage" of 10% ethanol in gasoline -- it raises the octane number by about 2 numbers. So it raises 87 octane regular to 89 octane mid-grade.

- Blending 10% ethanol in gasoline results in less energy content per unit (gallon or liter) than 100% gasoline contains. The loss of energy (at 10% ethanol) is about 4% or so. Less energy will result in reduced gasoline mileage (all other factors being the same). But the loss is so small (4% -- and sky-jumper may be correct that it's actually closer to 1.5%) and all other factors are almost never the same, so the loss in mileage is frequently hard to see -- but it is there.

- Using gasoline with 10% ethanol should not be done in older vehicles for two reasons. 1) The ethanol does loosen deposits in many places in the fuel delivery system. This can cause problems. 2) Vehicles built before about 1985 or so did not have gaskets (and in some cases even fuel lines) that were resistant to ethanol. Ethanol caused these materials to expand and fail. When ethnol became more prevelent in gasoline, all auto manufactureres changed to materials that could stand up to 10% ethanol in the fuel.

- Mandating ethanol in gasoline is a political decision and not an economic decision. The extra oxygen that 10% ethanol provides was supposed to improve fuel combustion and reduce pollution. But this was only true for older vehicles that did not have oxygen sensors. Those with an oxygen sensor simply adjust for the extra oxygen or adjust for no extra oxygen -- each type of fuel is properly burned based on these sensors. Mandating ethanol was a political decision that started with "needing the extra oxygen" and ended up with "it reduces our need for inported crude oil."

- But when you look at the net energy required to produce ethanol versus the energy content of the ethanol, there is very little (if any) net energy gain (depending on how you value the "mash remains" after making ethanol). You need to measure the fuel needed to plant, fertirlize and harvest the corn. The energy needed to produce the fertilizer. The energy needed to distill the ethanol. All of this energy used to produce ethanol is more than the ethanol contains, unless you provide some energy value to the used mash -- basically cattle feed. When you do that, there is a very small net gain in energy. But why bother -- politics.

- So mandating ethanol is a political decision to please the corn farmers and those like ADM who make ethanol -- and most of the profit from the government mandate. The farmer believes it's done for him but ADM (and other ethanol distillers) take the lion's share of the profit.

 

Ethanol is not mandated in Canada. Locally there is only one company that provides ethanol-based gasoline and I don't know if it is available in other regions in Canada. As mentioned, I believe it is wheat based and is certainly not corn based.

SilverMax04 raises a good point that I will have to look into. I started using 10% ethanol gas in my mom's 1985 Chrysler Avenue 5th Avenue with the 318 cu. in engine starting early in the year. The car no longer diesels (runs on) after being shut off as it did in the past in colder weather. She used to dump methyl hydrate into the gas tank in the winter, but no longer needs to do this. The car sits for extended periods and only has 65,000 miles on it.

I will check with a stealership to see if there are any adverse implications of using ethanol-based gasoline in this vehicle, given its age. The car doesn't even have fuel injection, just a two-barrel carburetor, lol, and has never run better.

 

to add more fuel to the fire (pun intended) check out the EPA report on RFG gas and fuel economy...
http://www.epa.gov/OMSWWW/rfgecon.htm
their data is a bit more optimistic about RFG than other reports I've read, but you have to consider the source (heavily biased toward RFG).
What I found interesting is they claim energy content varies even more for winter vs. summer blends of the same type (RFG or "regular") than it does for RFG vs. "regular" -- and from "batch to batch" of the same type (presumably from the same refiner). silvermax - can you confirm this??

btw - I think I stand corrected on my previous statement that, due to the inefficiency of internal combustion engines, an X% increase in energy content does not equate to an X% increase in fuel economy (or vice versa) as much of the excess would be wasted as heat. according to the EPA report there is a 1-1 correlation, and thinking this through I believe they are correct - the efficiency term cancels out of the equation. ironically this actually goes counter to their agenda.

 

I have some information on this topic.

The variation in gasoline energy content from batch to batch for a given grade, from the same refinery, is quite small for a given mandated type of gasoline (type by season and location). There may very well be a difference in energy content between premium and regular from the same refinery for the same season and location, with premium likely to have more energy than regular. There can also be a difference in energy content between the same grade of gasoline (including season and location) from two different refineries.
Each refinery has a number of different hydrocarbon streams that are used to blend gasoline. Those final gasoline blends must meet a number of strict specifications and each refinery will blend to meet those specs at the lowest cost. A given hydrocarbon stream may well be more "costly" for one refinery than for another, so the second refinery would be more likely to put more of that stream into its gasoline than the first. The key is to keep costs to a minimum while still meeting (or in some cases exceeding) the mandated specs. The company I worked for had a refinery that typically made winter regular gasoline with 89 octane (not 87) -- in order to meet the other specs and keep blending costs to a minimum.

Back before the government had stringent controls on gasoline blending (prior to 1980-5 or so) oil companies would blend quite a lot of Butane into winter gasoline -- to increase the vapor pressure so that the gasoline would vaporize at very low temps. Back then, the limit to Butane in gasoline was vapor lock -- you did not want your customers' vehicles to experience vapor lock on warmer winter days. The volume of Butane is important because Butane has less energy (and is also cheaper) than other gasoline blending components, so winter gasoline had (in the past) less energy content than summer gasoline. (Butane does have good octane, so that was not a major consideration when deciding how much Butane to blend into a gasoline batch.)

Today government strictly controls the vapor pressure of gasoline (RVP) by time period and you no longer hear of anyone experiencing vapor lock. (The EPA also has a vapor pressure waiver for gasoline with ethanol -- because it will have a higher vapor pressure than the gasoline without ethanol.) This means that the difference in Butane content between 1)winter, 2)spring-fall, and 3)summer gasoline blends is much smaller than it was in the past. I'm surprised they are even raising this question -- because it has more to do with historic gasoline than current gasoline.

A final point: a reasonably high vapor pressure was much more critical for getting an engine with a carburator started than it is today when most engines have fuel injectors. In the past, many people in the northern states (and Canada) would carry a can of ether to spray in the air intake to help get the engine started. You don't see this today.

 

I tried once gasoline with 10% ethanol, and effectively I saw reduced MPG about 15-20%. (stated MPG loss are 3-5% so I understand now why VQ35 needs premium instead of regular gas.

 

In many locations in the States all grades of gasoline contain ethanol -- even premium. So the presence of ethanol does not indicate that the gasoline is not premium -- only that 10 % ethanol has been blended into the final product.

By blending 10% ethanol into 87 octane regular, the resulting octane of the blended gasoline is 89 octane. So ethanol is a reasonably good octane preformer.

Gasoline that will have ethanol blended into it has been made at the refinery to allow for this octane boost. So the resulting blend has the desired final octane that gets posted on the pump. There are not many (if any) oil companies giving octane away with ethanol blending.

You should not have seen such a big drop in your mileage. Suspect that other things were happening at the same time to drop the mileage loss even more than the expected 5% to 7% or so. Some vehicles (not the recent ones) actually show a mileage improvement burning ethanol -- because the extra oxygen improves combustion and thus engine efficiency.

 

The most accurate why to calculate MPG is to reset your trip meter at fillup and then divide miles driven by gallons pumped at the next fillup. Your per-tank numbers are estimates at best.

As for energy content, here's a chart from this source:

 

That table has averages and estimates. Every batch of blended gasoline has slightly different energy content.

The Research Octane numbers on this table show that this table was probably developed in either Europe or Asia. The Octane posted on US and Canadian pumps is an average of Research and Motor Octane = (R+M)/2 octane. As a general rule, you can subtract about 5 octane from a Research Octane Number to get the posted octane (this subtraction varies between 4 and 6, but averages about 5).

So our octane for the regular gasoline in this table would be 86 and not 87 and the octane of the premium would be 90 and not 91.

You can do the manual MPG calculation you recomend, but because it is very difficult to fill our gas tanks to the exact same level ever time we fill up, I believe that the computer calculated MPG is probably as accurate if not more accurate.

 

RON is just a different calculation than the USA AKI Index. All you have to do is subtract 4 from the RON number to get the AKI equivalent.

In any case, most, if not all North American refineries produce gasoline of all grades that must meet a minimum deposit control and performance requirement as stated here which most car manufacturers use.

As for MPG calculations, I have used many methods including the a car's computer estimate (and that's all it is) and if you usually fill up at the same station with correctly calibrated equipment, the variation in the amount of gas going into your tank per fill up is going to be less than a quart. With a 15 gallon fill up, that's not a big deal. Doing simple division is far more accurate than any other method.

 

Gasoline Sensitivity (that is the difference between RON and MON) is more nearly 10 (generally varies between 9 and 11). So the correct subtraction from RON to get the EPA's "Octane Index" (used in the USA and Canada) is more nearly 5, as reported in my post, above.

Over a number of fill-ups, I find that my manual MPG calculations and the computer's "estimate" are very very close -- when each set is averaged.

Not all refiners belong to the group that advocates "Top Tier" Gasoline Standards. The last time I heard, BP does not because they feel these standards are, in some cases, not good enough. I'm told that there are other refiners who make good fuel but don't "belong." Just saw the list -- Exxon and Mobil are not listed. Neither is Marathon, Ashland, Diamond Shamrock, or Sunoco (in the USA). All of these companies make good product, but have not signed up for this program. Three of the companies on the Top Tier list are not even refiners, but only gasoline marketers: Kwik Trip, Entec Stations and Quick Trip. But then the standards, other than additives, are fairly standard in the industry. All these companies on this list are saying is that they will put a certain level of additive into the gasoline they sell. Sounds good, but it is really not that big of a deal.

 

All I was saying in my first post on this subject that doing an unaided per tank calculation is a bad way to figure MPG. Maybe I wasn't clear.

Regarding the chart I posted, I was just trying to point out the energy density of different fuels. I could really care less how the ratio of isooctane and heptane is calculated.