How much actual damage can 15% ethanol gas actually do to a car?
Posted by Humble_Handler93@reddit | askcarguys | View on Reddit | 114 comments
Been seeing a lot of reports that the US and several other countries are going to start diluting gasoline with 15% ethanol in an attempt to reduce prices. I’ve also seen many of these reports mention that older cars and enthusiast cars are potentially going to damage themselves using it regularly.
Is this true? What sort of damage are we talking about? And assuming it does cause issues how long before we start seeing them come about (as in how many fill ups would it take)?
I drive an 2002 Toyota Avalon and I’m really trying to keep it alive and well for at least another year or so, so I’m concerned that this new fuel might accelerate it’s decline
julianna884@reddit
I’ve been seeing so much fear mongering about this on tiktok and I was like really there’s no way it’d cause this much damage. Was gonna do some research about it later bc that seemed outrageous to me
casualcorey@reddit
but what?
milesdriven@reddit
Gasoline has been 10% ethanol for 25 years or so (with the exception of rec fuel, which is sold at and near marinas and costs $1/gallon more). Just keep using 87, don't use the "unleaded 88" which is 15% ethanol.
MidwestAbe@reddit
Why?
milesdriven@reddit
Too much ethanol can damage fuel systems that aren't designed for it. I use ethanol free recreational gasoline in all my small engines because I got tired of rebuilding carburetors.
Zealousideal-Fix9464@reddit
If you're rebuilding carbs then adding gaskets that are alcohol friendly will solve your problems.
ronisolomondds@reddit
My carbs have tons of brass parts inside that simply won't appreciate the increase in ethanol. Same goes for my older cars with mechanical fuel injection.
MidwestAbe@reddit
Engines decades old in vehicles are perfectly fine dealing with e10
IOI-65536@reddit
You missed the point of the question. There is a current effort to replace all the regular fuel with 15% ethanol. So if you're correct that 15% ethanol is too much then the answer to OP would be yes it will damage your engine.
I'm unsure. Small engines are actually generally designed for no ethanol so I can see 15% being too much for a chainsaw or lawn mower. Current car engines have gaskets that are ethanol safe so the question is going to be if the ECU and fuel delivery can adapt to lower energy density and I honestly have no clue how much it's going to cause problems. The EPA says you can use 15% on anything after 2001, but a lot of manufacturers say not to...
Legitimate-Duty-5622@reddit
I think you may be out a loop. If you live in the US, we’ve had at least 10% ethanol for about 20 years in all gas grades.
Freebirdhat@reddit
You can find ethanol free gas all around the country, nearly [18,000 stations] (https://www.pure-gas.org/). It's more common in rural eras where ranchers/farmers have known the detrimental impact of corn in their fuel for decades.
Legitimate-Duty-5622@reddit
They charge plenty extra for it too.
ronisolomondds@reddit
What is hilarious is E0 90 is the base fuel in NYS, and it costs significantly more than E10 93.
DFLDrew@reddit
Uh, not all gas grades. Many states have ethanol free premium
Odelay45@reddit
and a few of us live in states that also offer 87 Non-Oxy along with ethanol free premium.....the lawnmowers, snowblowers and boats love that ethanol free 87
ronisolomondds@reddit
It's E0 90 in NYS, which is great for classics and boats.
Legitimate-Duty-5622@reddit
15% ethanol will not upgrade your car any faster or at least not noticeably faster. You already had the game if you have a Toyota.
matt2085@reddit
I don’t think anyone said your car will go faster or further with more ethanol. Ethanol has less energy than petrol. Ethanol also absorbs water, that’s my concern with increasing ethanol concentrations.
StimpyMD@reddit
They just mix the ethanol with crappier gasoline.
Toss 83 octane gas with some 114 ethanol to make 87.
No benefits received.
Humble_Handler93@reddit (OP)
Yeah sorry, not much of a car person but I’ve had to commute a ton for work lately and I’m trying to keep the Avalon alive as long as possible so only recently started really trying to educate myself on cars and how to maintain them
Krutchd@reddit
0 damage.
Xxxzavierh123@reddit
Depends on the car, my 2013 juke really doesn't like it, pretty sure they swapped to e15 months ago before they had permission as my fuel efficiency dropped in a way consistent with that fuel type. Been getting misfires lately too. Your gas cap should say which fuels are okay for your vehicle, if it says only use premium, e15 aint great for it
Cold_Specialist_3656@reddit
US cars? Basically none.
Cars sold in US are E10 compatible since 2001. All of them used closed loop fuel control. E15 is basically the same as far as the car is concerned
Cynyr36@reddit
What about my car from 1999?
krombopulousnathan@reddit
Antique owners like you probably know more about the fuel requirements. There’s no way e10 or less will not be available; you just might have to go for midgrade or premium.
And remember when they say e15 it’s up to 15%. It’s often less.
This is a challenge with e85 tuning; a lot of time there’s not enough ethanol in the e85 to make the big power numbers so we have to run flex tunes
Cynyr36@reddit
If only it were some sort of "special" car, a 1999 saturn isn't. It's literally just still my daily. Tbh, I've been running whatever 87 octane is for the life of the car. My point was there are still older cars on the road being driven as normal cars and we should really do a better job about requiring labeling at the pump about what comes out.
(Also we ahould just plant solar panels instead of corn and make the cars run on electrons instead of needing to burn things.)
BadRad245@reddit
Every pump I’ve used says that unleaded can have hp to 10% ethanol in it.. have you been to one that doesn’t have that sticker?
krombopulousnathan@reddit
Sounds like you need an LS swap for it
Cynyr36@reddit
I was thinking more a prius swap or maybe an EV conversion.
Maybe a Kubota Diesel swap?
krombopulousnathan@reddit
Kubota swap and run it off propane!!
finnbee2@reddit
The corn lobby is strong. It will be difficult to get ethanol out of gasoline. The current government will be doing nothing to enhance the production of the solar industry.
Cynyr36@reddit
Ohh, i know its very strong. If i was a small farmer I'd seriously be looking at the return of planting solar vs corn or even a mix of them. Seems like solar would be less work long term, even less if I'm just leasing the land.
Electrical_Sun_7116@reddit
Non-ethanol gas is available in my area and generally called “boat gas”. It’s about the same price as premium.
krombopulousnathan@reddit
Yea around me it’s called “ethanol free” gas. We have it at Wawa and some local stations
Rusty_Bicycle@reddit
My 2002 Honda Accord doesn’t mind E-10. Of course it only has 110,000 miles on the odometer.
lethargicbureaucrat@reddit
My 98 Accord doesn't seem to mind E-10, and it's got 200,00 miles on the odometer.
Interesting-Rope-950@reddit
My 96 Corsica doesn't mind e 10 and it has 112,000 miles
Cars_Music_GoodTimes@reddit
It depends on the manufacturer. If it’s a Ford, they have been E20 safe since the early 1990s.
Interesting-Rope-950@reddit
What about Chevy? I recently got a 96 Chevy Corsica and I'm worried about this new gas blend. Is there anything I can add to the tank to help?
Cynyr36@reddit
Saturn with an engine designed in the early 1990s, and production ended in 2004. I've been running e10ish for a long time so if ethanol was going to damage hoses, seals, injectors it would have by now.
MountainFace2774@reddit
I used to own a 1993 and a 1995. I started driving in 2005. Those cars ran like shit on E10. No power and bad mpg. Now, it didn't damage them in any way but they certainly didn't like it. E15 would likely be worse. I regularly run E15 in my 2010 and 2020 vehicles and I don't notice a difference from E10.
milesdriven@reddit
I have two 90s cars and run e10 without issue. I did have an issue with my 81, but rebuilt the carburetor with ethanol resistant components and replaced the rubber fuel lines and then had no issues.
MountainFace2774@reddit
My 93 Toyota pickup and 95 Chevy Astro felt like I was pulling a heavy trailer with E10. The guy I sold the pickup to confirmed it. I had to run E0 or they ran awful. Both EFI. Maybe they had other problems.
AKADriver@reddit
Same. Been driving since 1997 and owned mostly '80s and '90s EFI cars well into the E10 era, still have a 1993 car on stock ECU and injectors. No noticeable power difference, fuel economy difference was measurable but not otherwise noticeable (not stopping for gas twice as often or something, but if I tracked mileage between fillups I could get a small bump if I filled with E0 in line with the slightly higher energy density/stoich ratio).
Past-Judgment-9700@reddit
Funny, I just made a comment on this..
My motorcycle is a 1999 and it will stall, apparently because of the ethanol. I have to update the fuel map in the ECU tune to adjust it to the ethanol.
JCDU@reddit
Probably fine - they didn't all magically switch in 2001, they knew the change was coming so any new models developed in the coming years would have had the necessary changes too - likely most cars from the 90's would be fine unless they're a design that was already old.
TDot-26@reddit
Most Mazdas are fucked as the manual specifies a max of E10
Cold_Specialist_3656@reddit
Doesn't really matter. Engine will compensate
TDot-26@reddit
I'll trust the people who created it
Humble_Handler93@reddit (OP)
Phew 😮💨 I know I can expect lower fuel economy as well but do you have an idea of just how much lower? I get usually 28-30mpgs currently.
badhoopty@reddit
i notice a slight difference with ethanol vs non-ethanol in my 98 4runner, its not so much that i gain any value from running non-ethanol. the lower fuel economy kinda balances with the lower price of the e10.
therin_88@reddit
Don't listen to that guy.
E15 in a car that's only rated for E10 could cause longterm damage to rubber seals and gaskets and hoses, will absolutely have increased wear on injectors and fuel pumps, and will make the car run somewhat worse, though that may not be noticeable depending on the car. You'll definitely have higher ignition temps and run a bit leaner, but most cars can adjust for this if they have an ECU -- it's called fuel trims, it just measures the O2 pre-cat and can tell the ECU to add more fuel.
I would NOT use E15 in any car that hasn't specifically been certified for it.
Now, as to some questions about pre-2001, there are other issues. Many of these cars shouldn't even have E10 in them for long periods of time, as ethanol is hydrophilic. This means if there's any way for humidity to get into the fuel system, it will. That will end up creating a gummy mess in your fuel tank and can also destroy your fuel pump.
Cold_Specialist_3656@reddit
Bro, you're bullshitting. Ethanol burns cooler and engine enriches mixture to keep things stoichiometric. It's exactly the opposite of what you claim
Cold_Specialist_3656@reddit
Hardly any. Ethanol helps prevent knock so engines run more advanced timing which mostly compensates
Pimp_Daddy_Patty@reddit
You probably won't notice the difference.
Humble_Handler93@reddit (OP)
That’s good to hear. I figured it was mostly fear mongering but I wanted to do some research on it myself
Citycrossed@reddit
I worked in the emissions industry and helped test E15 an E20 and its effect on cars and fuel systems. Essentially, there weren’t any issues. You’ll be fine. E15 has about 1.5% less energy than E10 iirc. You won’t notice the difference.
NoEmu5969@reddit
Did you see a difference in oil contamination? An old timer tractor mechanic once told me that e85 makes 10,000 mile oil changes feasible because it leaves less abrasive soot. Did you test the oil?
Citycrossed@reddit
We did oil analysis but only to look for any concerns, of which there were none. That's an interesting take on E85, I've not heard that before.
NoEmu5969@reddit
I’m playing with it in my Saab V4 because it’s prone to overheating. I should Blackstone a sample after 10,000 miles for funsies. Previous experiments with new vehicles have shown O2 sensor codes but no real problems.
Zealousideal-Fix9464@reddit
It makes sense, alcohol burns cleaner with less byproducts.
HoldingThunder@reddit
I am not discounting your experience but what I am seeing online is that it is about 77% as energy dense and the tests I am seeing online are getting 20+% lower fuel economy.
Care to explain the difference in values?
Citycrossed@reddit
E10 contains about 3% less energy (BTu/gallon) than E0. E15 has about 4.5% less than E0, or 1.5% less than E10. Not enough to actually notice for most drivers. Oddly enough, my best mpg in my 2020 Outback was on a tank of E15 but I was highway driving and not in a hurry. As always, the biggest factor in fuel economy is the nut behind the wheel.
HobsHere@reddit
What you are describing is E85. The post is about E15. Very different things.
Cynyr36@reddit
The E# is the percentage ethanol. So E15 is 15% ethanol and pretty close to the E10 that is whats generally available.
E85 is about 75-80% vs pure gas though, but that's not really part of this discussion.
Also the E# is an "up to" sort of thing as well. So just because it says E15 on it, doesn't mean it has 15% ethanol.
DatCarpet@reddit
It really depends on the car, I’ve had cars make no difference at all, some make 1-2mpg less and others take a 5-7mpg hit, they all still ran good though.
HoldingThunder@reddit
E85 is only 77% as energy dense as E90 fuel.
Pimp_Daddy_Patty@reddit
We're not talking about E85
IAFarmLife@reddit
The average I have seen is E15 is about 1.5% lower than E10. So 30mpg becomes 29.5mpg.
Tobazz@reddit
Well, all 3 of my cars were made 1998 or later 🤣🤦♂️
HoldingThunder@reddit
Except that ethanol is less energy dense than gasoline. E10 has an energy density of 33.18 MJ/L vs 25.65 MJ/L. Even if it's cheaper, you are getting ripped off. You are only getting 77% of the energy in a tank so it only make sense to buy if it's that much cheaper than normal gas.
IAFarmLife@reddit
It's not a 23% reduction in energy. E10 has about 3-4% reduction vs E0 and E15 will be an additional 1-2% lower. Most drivers see a 4% reduction in fuel economy in real world driving situations. At 11% less cost at the pump E15 is the better value.
Your costs and average economy may be different. This is based on averages across multiple vehicles and my local fuel prices.
Difficult_Plantain89@reddit
I think you are mixing up E85 and E15.
Counting-Tiles4567@reddit
JFC the number of incorrect pedants here. 1) E10 or E15 is 10% or 15% ethanol and 90% or 85% gasoline, which itself is a mixture of alkanes, alkenes, additives, and "aromatics". 2) The US has used E10 as a standard "oxygenated" blend for ~30 years. 3) Ethanol CAN attack some "rubber" namely, Neoprene and Nitrile. This IS a problem for carbureted systems--especially older ones. Cars older than 25 may have rubber fuel system components that could be compromised by higher ethanol levels, but I have never seen it working on "corn country" cars (where e15 has been sold for a long time) 4) Most modern cars have fuel systems that use Viton, fluorosilicone, or Teflon. They will feel "plasticky" vs "rubbery". These systems are generally speaking immune to ethanol below E50 (50% ethanol). 5) Ethanol attracts water more than gasoline. This is a big issue if the fuel sits in your tank for a long time. This means months of sitting through seasons. 6) Ethanol doesn't have the same lubricity as gasoline. At very high levels of ethanol, or greater than ~50%, you need a specially rated fuel pump to handle this fact. 7) Ethanol burns cooler, slower, and with much higher effective octane than gasoline. 8) Ethanol requires a lower stoichiometric ratio than gasoline, so, ~10 parts air to one part fuel, vs ~15 for gasoline (from memory, but close). However, an extra ~33% more fuel on 5% ratio change (e10-->e15) is ~1.7% change in injected fuel charge. This is well within the +/-15% most cars can "trim"(adjust) the amount of fuel injected as per their air fuel sensor feedback.
Engines LOVE ethanol in fuel. SOME older fuel injection/carbureted systems DON'T. You're not going to "blow" your motor, at all. Modern cars in the USA are designed to handle upwards of e20 without issue. The government knows this, which is why they're pushing this through.
Freebirdhat@reddit
Cons: 5%-20% less mpgs, it wears down gaskets/seals/hosing which if not monitored can result in shorter engine lifespan. Because of subsidies, it has increased the cost of corn products in the US, corn is in 50-90% of what we consume.
Pros: Because of subsidies, we see a cheaper price at the pump and get gratification. (Traveling less per gallon and hidden maintenance costs more than offset this)
IAFarmLife@reddit
In real world driving conditions E15 averages 4% less mpg not even close to 20%.
Oil has subsidies too. You can't say ethanol is cheaper because of subsidies without acknowledging that the industry as a whole receives subsidies.
Supply has been keeping up with demand for corn. Farmers went through an extended period of very cheap corn that almost always received LDP payments since it was below the cost of production. By raising corn prices to actually turn a profit this has resulted in increased research for corn production and the results are much higher efficiency benefiting everyone. When adjusted for inflation the corn price is actually much lower since ethanol production began.
Freebirdhat@reddit
Ethanol has 40% less btu than pure gas. It's not some magical substance that ignores chemistry and math. Depending on the blend you are getting between 4%-34% less energy per gallon. In the real world these numbers are worse because ethanol evaporates at a faster rate.
double-click@reddit
Ethanol is hygroscopic so over time the water can separate and cause issues. If you drive your car regularly this won’t be an issue.
Otherwise it has less energy per unit than gas.
EventHorizonHotel@reddit
They are just making E15 more available, E10 based gas will still be available
Icy_Site_7390@reddit
Boat engines are very unforgiving when it comes to water and ethanol pulls water out of the air will screw up boat engines big time
MichaDaFox@reddit
People are telling you that you specifically are fine (and you are), but never address your question.
On old cars (think early 90s and older ODB1 or no ODB at all cars basically) most cars are only designed and Rated for E10 or M5 fuels. Long term exposure to higher concentrations of Ethanol or Methanol will cause damage to some fuel system components on these old cars. It will make the plastic screen / filter on most old style fuel pumps brittle. It can make un-lined hard fuel lines and tanks rust because of the moisture it traps. It will harden rubber seals ( think check valves, diaphragms on fuel pressure regulators, or gaskets in carburetors) which will cause leaks or impede function. The extra moisture and properties of ethanol mean things like pintle valves ( carburetor and fuel injectors ) will clog or have poor atomization over time because the fuel and moisture is more likely to gum up (ethanol fuel spoils much faster than petroleum fuels as it absorbs water)
Additionally, you need to compensate for the reduced power density of ethanol ( IE you need to use more fuel per combustion event). Modern cars this is no real issue. But early MFI and EFI (70s/80s) cars like K-jet and L-jet based systems are limited in the compensation range (and usually can only run the long term fuel trim in a 5% +/- from ideal) The car will run, but it will run leaner than it should which can lead to hotter combustion chambers, increases engine wear, loss of power etc. You need to either flash the EPROM to a richer fuel map which is not always possible, or you will most likely run larger injectors that use the stock fuel map. The higher the ethanol concentration, the more likely you will need to modify the fuel delivery.
therin_88@reddit
Listen to this guy, not the doofuses telling you that it's no different from E10. If it was no different from E10, they would've replaced all E10 years ago and charged you the same for it, because E15 is cheaper.
WorkerEquivalent4278@reddit
I’ve seen BMW motorbikes that won’t even run on E15. Drain that junk and refill with regular and they run fine.
therin_88@reddit
E15 in a car that's only rated for E10 could cause longterm damage to rubber seals and gaskets and hoses, will absolutely have increased wear on injectors and fuel pumps, and will make the car run somewhat worse, though that may not be noticeable depending on the car. You'll definitely have higher ignition temps and run a bit leaner, but most cars can adjust for this if they have an ECU -- it's called fuel trims, it just measures the O2 pre-cat and can tell the ECU to add more fuel.
I would NOT use E15 in any car that hasn't specifically been certified for it.
Now, as to some questions about pre-2001, there are other issues. Many of these cars shouldn't even have E10 in them for long periods of time, as ethanol is hydrophilic. This means if there's any way for humidity to get into the fuel system, it will. That will end up creating a gummy mess in your fuel tank and can also destroy your fuel pump.
WiseSubstance783@reddit
I thought part of the issue was that with older cars that the ethanol would eat the rubber lines of the fuel hose or something
Branded_bottle33@reddit
No damage unless you’re gonna let it sit unused for months and in that case you should’ve been using ethanol free gas previously. Ethanol actually burns colder than gas and is used in enthusiast cars with a tune to crank out some extra horsepower. Only real downside is that it burns quicker.
Humble_Handler93@reddit (OP)
Good to hear, I’m certainly not going to let it sit. I commute about 1000 miles a week so it’s definitely not sitting 😅
Zealousideal-Goat839@reddit
1000 miles a week? You're one of the few people that can justify a new car every 3 years haha
Humble_Handler93@reddit (OP)
It ain’t by choice 😅
I wish I could afford a “new” used car let alone a brand new car
rickhamilton620@reddit
Just noting for any Mazda drivers with the SkyActiv engine that see this - Mazda says E10 max period.
Definitely an outlier compared to Honda and Toyota, it’s worth checking your manual just in case.
boxwhitex@reddit
Most new cars are turbo, it will most definitely run worse and not be as efficient. It's going to be a scam on the people, as prices will be the same but a gallon doesn't go as far.
Obsession88@reddit
Has anyone tested e10-e15 to see if they are actually 10-15% ethanol? I run e85 in my fun car, test the percentage every so often and know the range varies a lot.
noah_fechts@reddit
I think it’s very bad for carburetors. I have an old car using an Italian made Weber IMB28 and had to rebuild the entire fuel system. It didn’t correct all the issues, so I had to rebuild the entire engine, a small 595cc. The previous owner ran it exclusively with E10 and had let the car sit for a year or two.
Now I’m certain all the damage wasn’t due to ethanol alone, but I don’t think it helped. I think the biggest issue is the water and doesn’t “burn” as well as E0.
publicsausage@reddit
Carbs aren't inherently an issue the problem is that the gaskets and seals weren't designed for use with alcohol, it dries them out and degrades them. You can rebuild the carb and fuel system with alcohol compatible ones and it'll run fine. Other issue is alcohol isn't as energy dense so you'll need to jet it up for more fuel at the same output.
imissher4ever@reddit
I’ve been running regular pump gas in my classics for decades without issues. In both Solex and Holley carbs. I don’t keep a lot of fuel in the gas tanks. I generally keep less than 1/8 of tank unless they are being driven somewhere.
Cars_Music_GoodTimes@reddit
15 years ago, I worked on a study of e15 fuel in vehicles from 1996-2006. The study found that nearly all manufacturers in the USA were using e15 safe materials back in the 1990s.
Your 2002 Toyota will be fine on e15 fuel.
ClickKlockTickTock@reddit
None. Any car that isnt 30 years old can handle at least 80% ethanol fuel, required by law. They aren't required to run on up to 80% fuel, but running a tune is much easier than replacing fuel tanks and lines and injectors.
Apprehensive-Read989@reddit
That's not true. There are a lot of cars made very recently that are not designed to handle anywhere near E80. My 10 year old truck can only do E15 and that same engine was used all the way until 2024 in North America, it's still in production outside of North America (Toyota 1GR-FE if you want to look it up).
WhyNWhenYouCanNPlus1@reddit
my related question is what would need to be changed for a car to run on pure or nearly pure ethanol (or methanol)?
alcohol isn't cheaper to make than current gas prices but it's easy enough to make from domestic ingredients
HobsHere@reddit
Many will as is. Others, you may need to install higher flow injectors, at least if you want full power. A common weak point is the gas tank level sensor. These will often fail in high percentage alcohol use.
Chockfullofnutmeg@reddit
Pure ethanol might require different fuel injectors and/or ecu tuning to accommodate the higher fuel volume.
ttypeguy@reddit
It's the small engines lawn mowers and weed eaters from early r going to hurt
malsell@reddit
There will be reduced fuel economy and power for some vehicles. The biggest problem will be water absorption into the fuel for people who don't drive very often. 8 have an EV and an ICE car. I really only use my ICE for long trips, so I may not use a full tank for a couple of months.
N47881@reddit
If searching for uncontaminated fuel, look no further www.pure-gas.org
robert32940@reddit
Another bail out for the corn lobby?
Nervous_Olive_5754@reddit
It was 10% ethanol for most people most of the time before. In the midwest, they've had 15% available cheaper next to the other stuff if you want it in some places for a while. This has been the case for years.
It's generally several percent cheaper and get slightly less mpg. So you're getting an opportunity to save very little on gas.
fucku12345567@reddit
My car drives noticeably faster with 10+ percent ethanol It’s different enough that I go out of my way to make sure the fuel has ethanol in it when I buy it.
The difference between regular gas and premium with ethanol is worth getting the premium. Literally night and day.
Nervous_Olive_5754@reddit
It's probably designed for premium in that case.
yeeting_my_meat69@reddit
Damage? None if your car has been running the e10 that has been standard for decades.
The savings would be mostly offset by a decrease in fuel economy. Ethanol is roughly 30% less energy-dense than pure gasoline. Your car compensates for this by burning more fuel to make the same power. You might net a few cents per gallon, but not enough to make a huge difference unless they are selling the e15 for significantly less money.
Affectionate-Act6127@reddit
The handwringing over E15 is almost entirely made up.
Vapor pressure of gasoline is regulated by federal law with standards set in 1970. Automotive technology has changed since then with fuel injection and three way catalytic converters.
A 1990 carve out for E10 allows for +1 psi vapor pressure, but gas pollutes the same at same vapor pressure.
If you have a lead foot, E15 is slightly less efficient than E10. If you have a lead foot, fuel economy is a legitimate concern for you.
On a cost per mile basis E15 isn’t diluted.
biggunzcdb1@reddit
Depends on age. More than 25 year old cars are the concern. But even then it's super slow damage. And the parts it damages are probably due for replacement anyways. If your car is 25 years old it probably needs a fuel system upgrade anyways.
Prestigious-Hyena-72@reddit
Doesn’t out gas in USA contain up to 15% e?
krombopulousnathan@reddit
Currently 10% is the norm.
We have some stations that are e15 but it’s not all that common. My partner and I go for it because our cars are newer and it’s much cheaper. We only notice we lose about 1 mpg on e15 vs e10 at most. Some tanks we recorded were no difference at all.
Potential_Stomach_10@reddit
E15 or 88 octane has been around in PA for some time. I ran it in my old Camry for about 6 months. Lost maybe 3 mpg and it was 20 cents a gallon cheaper