I have what at least for me is an odd question. I’ve had my 2007 Camry hybrid since new and have consistently averaged in the 38 to 40 mpg range in warmer weather and more in the 35to 36 mpg range during Minnesota winters. Over about 60,000 miles, my highest tank was around 43.
On a recent tank that consisted of about 75% highway driving, mostly 60 – 75 mph, my mileage jumped to my highest ever tank average of 44.4 mpg. And now this week with about 400 miles on the tank, I’m just over 45 mpg. The temperature has been warm and my tires (Nokian WR) are nearly warn out, but there is nothing different about these last 2 weeks. All trips have been round trips on the same day, so there can be little impact from wind direction, up hill, down hill, etc. I’m completely baffled at the reason my mileage could jump by 10% or more just suddenly. The gas used is the same including 10% ethanol, car has not been serviced, no change in tires or pressure, nothing. Actual mileage calculation shows the dash computer is slightly high as always but close enough. Any ideas; I’d definitely like this to continue.

 

If your local stations sell 10% ethanold gas and you got outside of your local area and bought 100% gasoline, that would definitely explain your increase in mileage.

Unfortunately, more and more of us are being forced to buy this E10 garbage and our gas mileage has gone down as a result.

 

Good point Joe.

The TCH seems to get it's highest mpg in 70F to low 80F degree temperatures. Driving in the warm afternoons when the humidity is usually at it's lowest. (no AC) Any low or no wind also helps.

 

Agree, the temps have been ideal in the 75F to 85F range, but all gas was with the hated 10% ethanol, and there would be little to no wind advantage or disadvantage because all trips were same day round trips. Still can’t figure it out.

 

If I had to make wild guess, schools are closed so little bit less traffic (not sure how much traffic is an issue at your location) also in summer I drive more on a longer, leisure trips and less on the errand side, short trips, which are mpg killers. Also I thought some fuel additives were mandated in winter to lower pollution, but not in the summer, but then this may vary from state to state. I'm sure your MPG will get back to "normal" soon. BTW, funny thing is I also was getting 38-40 summer, 34-36 winter and my best tank is about 43 and also I've seen 45-48 mpg in ideal driving conditions for extended times, albeit they never lasted full tank, after all it's about 600 miles before the tank runs dry.

 

There's just too many variables, or a combination there of, to explain a modest 3-4 MPG increase. Fuel is the usual suspect, followed by weather, followed by driver teqnique. The rest is just luck of the odds. Did you make more green lights and have fewer red lights for example?

BTW, it is a bit short sighted and pre-mature to "hate" 10% ethanol in gas.
People did NOT want to switch to unleaded gas, or lead-free paint for that matter. People did NOT want to change for chloroflourocarbon CFC propellents in hair spray and air conditioner's, but here we are.
A better, hopefully healthier planet.

If you "love" pure gas, then it is safe for me to assume you also love leaded gas, leaded paint, ozone depleating propellants, DDT, mercury batteries, mercury light bulbs, ivory, and whale oil.

You are very short sighted if all you can see is miles per gallon.
( And in that case you should be driving with diesel... shame on you for using gas in the first place! )

 

gspman1, Thanks much for your helpful insights and clairvoyance as to my motivations and qualifications.
Just a couple thoughts… In over 40 years of environmental research (wrote my first paper on climate change in 1970, drove my first 38 mpg car in 1971 Audi Fox), I’ve almost never read such concise brilliance as your above comments. I assume you work for ADM, but the rest of us might want to consider today’s news headlines - literally this morning. Small grain prices (wheat) are the highest in history; real and widespread starvation is on the horizon for the Middle East and Northern Africa because of the current grain shortages. It really is a clever strategy to dedicate even more of our most productive farm land in the world to produce ethanol for an arguable 10% net gain in BTUs. Oh agreed, cane sugar ethanol is more efficient, so let’s encourage Brazil to burn the last vestiges of the rain forests to make more ethanol. Great trade-off.

The only good use for the corn ethanol production in the US is Shaker’s Vodke. Drink a couple quarts, calm down and buy all the ethanol plant stock you can. We’ll all be rooting for you.

 

DO NOT assume anything about me....you don't know me, nor my beliefs.

10% ethanol reduces gas mileage; lead-free gas has proven results in air quality, longer engine and powertrain life, and many other benefits; 10% ethanol reduces gas mileage in a car I specifically purchased for its gas mileage. .

You were WAY out of line to make those statements.

This is the same kind of flawed logic that says anyone who disagrees with President Obama is a racist--convenient, but very, very wrong. Please do not assume that an assumption of being right is a license to be arrogant or rude.

 

More short sightedness.

Wheat prices are high because of draught in Russia. A temporary condition, not related to ethanol.

Since ethanol took off in the last decade, bushels per acre has gone up, number of acres planted has gone DOWN. ( less land use )

Since ethanol took off, the amount of grain exported to foreign nations has steadily risen.

Since ethanol took off, the price for animal feed has gone down. Animals feed people directly (hamburger, chicken patties) or indirectly ( milk & eggs ).

Ethanol only uses the sugar out of the corn. The protiens and fats of the corn still are used for the animal and human food chain. Look it up. Don't take my word for it. In your research you will see there is a world-wide shortage of protien, and a surplus of sugars and starch. ETHANOL does not use protien at all. Ethanol production provides LOW COST protein.

Since ethanol took off, there has been an AVERAGE of 2 billion bushels ( over 100 Billion pounds) of corn left over, at the start of the new harvest. It is not a question of where will we get enough grain, but a question of where do we store all the grain? Or would you like to pay farmers not to farm next year?

EVERY DROP of ethanol produced this year will grow back next year.
It is 100% renewable. It is carbon neutral at worst, and likely, removes carbon from the atmosphere as a small percentage of the bio-matter is actually converted to liquid fuel.

A 76,000 btu gallon of ethanol requires 14,000 btu to produce at a modern ethanol distillery. Go ahead and double that to include btu for transport of raw materials. Go ahead and triple that to include transport and growing.
You still come out ahead.

Gasoline production requires 150,000 btu to produce a 115,000 btu gallon of gas.

Ethanol production requires 2.5 (best) to 3.0 gallons (worst) of water to make 1 gallon of ethanol. Only 3% of the grain used in 2007 came from irrigated land.

Gasoline refinement requires 15.0 (best) to 40.0 gallons (worst) of water to make 1 gallon of gasoline.

You said it first, ethanol is drinkable. Gasoline is not.
Ethanol is non-toxic to animals, fish, and plant-life if diluted with 5 parts water or more. Gasoline is toxic in parts per million and cannot be diluted with water.

10% ethanol in gas reduces harmful tailpipe emissions by 26% to 38% depending on the study.

10% ethanol was not meant to give you more miles per gallon.
It is there to keep the air we all breathe cleaner, create millions of American jobs ( or homeland jobs, whatever nation you are in ), and make fossil fuels, that aren't going away anytime soon, last a little bit longer.

No one has died drilling for ethanol.
No one has died protecting ethanol fields in foreign countries.
No wars have started over ethanol.

The real cost of gasoline is about $18 to $30 per gallon.
The real cost of ethanol is about $1.40 to $1.90 per gallon.

The more you look at ethanol, the better and better it looks.
People who don't like it, probably haven't really looked into it very deeply.

I do not work for ADM, but I do work for an engineering company, and as part of my job, I have visited and conducted energy and efficency audits of 31 large scale ethanol production plants to date. Most were less than 4 years old. EVERY ONE was net energy positive and carbon neutral. I do not get paid based on my findings, and this is only a small fraction of my over-all job duties.

Most use 14,000 btu of fossil fuel per gallon and 0.40 kWh electricity from the grid per gallon of ethanol produced. EVERY ethanol plant produces roughly 1 pound of food per one pound of ethanol produced. SOME ethanol plants capture and compress the CO2, the bubbles in the beer for use as dry ice, fire extinguishers, other industrial purposes, or with additional refinement, for sale to coke and pepsi bottlers. Carbon recycling at its best.

Most studies you read that are anti-ethanol are more than 4 years old, and do not use up to date numbers and statistics. Most opponents to ethanol use data and studies from the 1980's. Let me ask you, what kind of computer were you using in 1980??? Ethanol's come a long way lately... big improvements in the past 5 years alone.

FYI with an octane rating of 115 for pure ethanol, and 105 for retail 85% ethanol, 15% gas, you can buy or build a high compression engine that will give you MORE miles per gallon, with the same displacement, as the car you are driving today. Small hybrid cars on ethanol could EASILIY exceed 100 Miles per Gallon. ETHANOL IS RACE FUEL!

MPG seems ultimately what you want. You should get on to ethanol ASAP!

 

Sorry, didn't think I was being more rude than anyone else.