Esteban

I have a 99 TL with 124K miles. Brand new air filter. Oil changes every 3K miles. Sparkplugs are NDK Iridium, replaced about a year ago. New timing belt. Tires are properly inflated. I averaged 22/23 MPG most of the times throughout the 3 years I had the car, with an impressive peak of 31MPG during an all-highway trip to Orlando. And yes, I ONLY use premium.

However, gas stations here in South FL have recently been adopting the 10% Ethanol blend, and, coincidence or not, ever since then my mileage has been a LOT worse. I now average 17 MPG, in a mix of about 60% city and 40% highway. My driving style has not changed. I rarely go over 2K RPM's. I even do 55 MPH on the highway with my cruise control on. My routes have not changed. But now I'm getting 5 to 6 miles LESS per gallon. That's a HUGE difference. I read that ethanol is supposed to reduce your mileage around 5 to 10%, but this is ridiculous. Anybody else experienced similar drops?

firstpickrick

Yeah, It's cause Ethanol is not as dense as Octane, thus having less energy, and ultimately leaving us with less MPG

fsttyms1

Yes. I see a sizable drop in mileage when im forced to run fuel with 10% (usually in the 40-60 less miles per tank). Here in Wi we still have gas stations that dont use it. Ethanol is a joke and needs to be yanked as an alternative fuel, and not be used as a mixture in gas.

Esteban

Yes, but is such a drastic reduction in mileage normal? Also, anybody know if one can still buy gas with NO ethanol in South FL (I'm in Broward)?

Esteban

Ah, exactly the same here! At least I now know it's not my car. Yes, this IS a joke. I wonder what kind of damage this does to our engines in the long run. Any additives that can be used to maybe counteract the effects?

fsttyms1

10% shouldnt hurt any thing other than the pocket book. Keep the car well maintained. Run seafoam on occasion in the fuel and thru the intake to keep things clean. Its about all you can do

Esteban

But in this case (and it seems I'm not alone), the result is more like 20%!

fsttyms1

10% is the max they can add to the fuel. Not the drop in mileage.

LukeaTron

Gasoline has an energy density of 34.8 MJ/L. Ethanol has an energy density of 23.5 MJ/L. That's a 23.5% difference if you were to run straight Ethanol.

At 10% Ethanol, the energy density of resulting mix would be 33.67 MJ/L (energy density of gasoline * 0.9 + energy density of ethanol * 0.1). That's only a 3% difference in net energy density.

There are other compounding factors at work however. For instance, the conditions required (temperature and pressure) to extract the maximum amount of energy from ethanol are going to be different from that of gasoline. Since your motor was designed to optimally burn gasoline, it is necessarily not designed to optimally burn ethanol.

Still, 20% feels like a pretty big drop. I don't know what the expected results should be or how to calculate them. The lamest thing about ethanol is that you're paying the same price but getting less usable fuel for it. Lame.

firstpickrick

Gasoline has an energy density of 34.8 MJ/L. Ethanol has an energy density of 23.5 MJ/L. That's a 23.5% difference if you were to run straight Ethanol.

At 10% Ethanol, the energy density of resulting mix would be 33.67 MJ/L (energy density of gasoline * 0.9 + energy density of ethanol * 0.1). That's only a 3% difference in net energy density.



Great Explaination

firstpickrick

great physics explaination.

kinghost1

Is it bad to use Regular Fuel (87) on a 03 TLP? I get the exact same gass milage with premium!

01tl4tl

Read the pumps at different brands in your area- or look at the makers websites for ethanol
its getting to be everywhere- used to add MTBE but it eats the Earth, so ethanol was the change. Why not use a now scarce food for fuel- sounds perfectly reasonable! too bad they have those floods now and the crops are destroyed---oooops

Seafoam if you have not before- and as kris said- now and then run it in the gas.
Thats good for a bunch of percentage points returned right there for $14 investment.
Inflate the tires a fee psi above normal- try 34 or 36 front, 34 rear and see what that does for you
Change the cabin air filter and especially check the engine air filter!!!

01tl4tl

the TL needs 91- especially the higher compression Type S motors
Sure the computer corrects as much as it can, but go on a trip and it shows the drop in mileage on the wrong gas

Another thing to consider is the brand of gas you use in the TL

It REALLY does make a differance to use Tier 1 branded gas- they are ones that contain certain cleaners and additives that are better that the cheap off brand gas.
Chevron-shell- texaco mobil-76-BP- are all listed- use internet search about it to find brands in your area
I know it seems smart to buy the cheapest gas these days- BUT it can pay you right back using the proper grade and brand

rob-2

FYI I'm getting between 30-33mpg freeway on 87 oc. I believe there is ethanol in my gas, not sure if it's 10%. Will check next week when I fill up.

20% drop its not from the 10% ethanol

aznboi2424

iTrader: (10)

you mean chemistry explaination?

Phrosttz0

ethanol sucks

aznboi2424

iTrader: (10)

x2

fsttyms1

No but there is a drop. I always see a 40-60 miles per tank reduction.

sb65

I had a noticeable decrease in mileage when my tranny started acting up. It would kind of shudder a bit going from 2nd to 3rd under soft acceleration, but that was about the only symptom. My avg mpg was consistently less than 20 and I could not figure out why. After I got a new tranny ... now back up to averaging 25+ with a roughly even mix of city/hwy driving. It would probably be 2 mpg more if I still ran the stock Michelin tires (noticeable drop when I put on Yokos).

phee

iTrader: (5)

gatorades better

Esteban

Yes, I also see a 40/60 miles per tank reduction. And the tranny is brand new, BTW. I got it replaced in February. Front two tires are also brand new (had Yokohamas Avid before, Hankook now... got them two weeks ago). Even the air filter is brand new. The car had been extremely consistent all the time, until they started using Ethanol here in FL... I wish I knew where to find a gas station with NO ethanol down here...

Johnny Canuck

For the time being at least , here in Canada Shell premium (91 octane) contains no, nada, zip ethanol. The two lower grades do contain up to 10%. Corn should be used for food products, maybe the left over husks etc can be used to make ethanol, same as sugar cane stalks. Ethanol has progressed too far in the "new" economy to suddenly dump the product as derived from corn. Bush, Cheney and their oil baron buddies know this as do the senators and lobbyists from the corn growing states. Less mpg means more frequent gas purchases at the pumps. Less corn for food means higher prices for corn. Less corn for food means higher food prices. Corn grown for food means less corn for ethanol production which means higher corn prices for ethanol. Jeez, do I detect a vicious circle here? As meaningless as it sounds and nothing will be done at this late stage but yes, ethanol production from corn needs to be cancelled 100%. Ain't gonna happen, nohow. JC

acutee

So, ethanol is not really helping anything with the gas crisis. It is just a way to make more money from consumers.

So, for instance, instead of using one gallon of pure gas to get to my destination, now I need 2 gallons to get to my destination, paying double. So, what is the point of using ethanol. My guess is to use the left over crap to create ethanol, and sell it as gas money; like fake wine vs pure wine.

dnd2984

iTrader: (6)

Yea that 10% is taken a toll. I am at 190 miles and exactly at the 1/2 tank mark.

rob-2

If the energy numbers present are correct, you'd really be hard pressed to notice a difference in mileage.

rob-2

Stupid, can't edit after 5minutes.

FYI - the same folks who said mileage would suffer with 87oc are the same scream poor mpg with 10% ethanol.

I would conclude that most of these opinions are hot air.

I just did a trip to reno and back, 440miles, 14.4 gals, including city and idling. That's 30mpg.

Kevin Briggs

How do your brakes look? How about a stuck brake caliper? Also, what do the brake hoses look like? I have seen where brake fluid doesn't pull the piston back due to contamination in the brake fluid or poor "O" rings in calipers causing them to stick and not return.

I wonder about clutch slipage in the transmission. When was the last time the trans fluid was changed? How about the transmision filter change? How about the ECM not allowing the trans to lock up? Do you notice the tach running higher than "normal"?

Just a few thoughts.

Esteban

Nope. Brakes are fine. Fluids are fine. And like I said in my previous post, I got a new transmission in February.

I just spoke to a friend of mine who drives an 06 TSX. He got it brand new two years ago. He drives similar routes than I do and probably uses the same gast stations here in South FL, and he's also experiencing a dramatic drop in mileage. He told me he now barely averages 230 miles a tank! On a TSX!

fsttyms1

Come fill my car and tell me the mileage and see if its hot air! I do more driving than 2 and 3 of you combined. There are only 2 other members that had more miles than me. Why would i/we make shit up? We arent the only ones. This debate has been going on since the start of the forum. While some (like yourself) havent noticed a difference many others have. Is that hard to believe? You dont see us saying your blowing hot air saying you get what you do. Maybe we drive harder which will show the difference. Doesnt matter. What works for some doesnt for others. Type-s owners especially need to pay closer attention to the octane.

Phrosttz0

i donno, my car hates 87, and hates anything containing ethanol..which equals horrible gas mileage, bitch is a 99 with 63k, religously maintained...

vtec260

The issue with gas mileage reduction is maybe op used NDK spark plugs instead of NGK. Perhaps NDK's are Chinese-made knock offs causing irregular firing? LOL

At least at my part of Canada, 91 octane is untainted stuff in summer or winter, so I hope it stays that way.

Just bought a couple of cans of seafoam for $6.99/can. How much is it in US? I am a bit hesitant to use it on my TL with 40K miles yet. I will try it in wife's van 1st with higher mileage.