Ethanol free?
MBWorld Fanatic!
Joined: Sep 2018
Posts: 3,247
Likes: 934
From: New Orleans Area
2015 E400 Sedan
91 is premium in Denver I think but where I live 93 is premium and 89-91 is midgrade
87 is regular.
I can only find regular ethanol free
yes more energy per gallon then any gas mixed with ethanol but I doubt one could feel it.
plus better mpg w/ethanol in fuel.
the Placebo effect is a powerful thing
87 is regular.
I can only find regular ethanol free
yes more energy per gallon then any gas mixed with ethanol but I doubt one could feel it.
plus better mpg w/ethanol in fuel.
the Placebo effect is a powerful thing
Junior Member
Joined: Jun 2023
Posts: 62
Likes: 21
From: South West of France.
2010 E550(S212), 2006 Chrysler Crossfire (SLK 320 R170 in disguise), 2012 CLS500 (x218)
Shouldn't it be the other way around and better mpg w/o ethanol as ethanol has a lower energy density?
Last edited by PEagle; Aug 23, 2023 at 07:31 AM. Reason: typo
Trending Topics
Junior Member
Joined: Jun 2023
Posts: 62
Likes: 21
From: South West of France.
2010 E550(S212), 2006 Chrysler Crossfire (SLK 320 R170 in disguise), 2012 CLS500 (x218)
From what I read and discussed, it's bad for old engines because it would dry rubber hoses that weren't thought for it. Other issues are that ethanol "cleans" your tank and so it will remove all the dirt in your tank and may plug your filter/injectors. It's also harder on fuel pump and may require bigger injectors as you need more fuel than with ethanol free fuel.
iirc, most of vehicules from 2000 on poses no threat, especially if diluted in "standard" gasoline.
Another issue is that ethanol captures water so if you have water, condensation or high humidity, ethanol will combine with it and sink to the bottom of the tank. That mixture is much less flamable and will have a hard time in your engine... and as it's sinking it'll be happening on startup.
I may miss other stuff but that's what I could gather from my own research.
iirc, most of vehicules from 2000 on poses no threat, especially if diluted in "standard" gasoline.
Another issue is that ethanol captures water so if you have water, condensation or high humidity, ethanol will combine with it and sink to the bottom of the tank. That mixture is much less flamable and will have a hard time in your engine... and as it's sinking it'll be happening on startup.
I may miss other stuff but that's what I could gather from my own research.
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
Super Member
Joined: Jan 2021
Posts: 557
Likes: 204
2021 Mercedes GLB250 4Matic
Ethanol or not the Octane number is what dictates how gasoline typically performs aka at what pressure it will self combust. The actual mixture could be different gas station to gas station. We had constant issues with Kawasaki utility vehicles, that kept braking due to cheap plastic fuel pumps effected by ethanol in the gas. As others said modern cars designed for it.
Junior Member
Joined: Jan 2022
Posts: 47
Likes: 10
GLB 35 AMG
Junior Member
Joined: Jun 2023
Posts: 62
Likes: 21
From: South West of France.
2010 E550(S212), 2006 Chrysler Crossfire (SLK 320 R170 in disguise), 2012 CLS500 (x218)
I don't know for you in the US but here in France, petrol company pretty much does that for US. Ethanol fuel is named E85 and is at max 85% Ethanol. They will vary the ratio of Gasoline and ethanol depending on the season to avoid hard startups in the winter.
But yes, cold startup is the worst as well as startups after a long period of non driving.
But yes, cold startup is the worst as well as startups after a long period of non driving.
Junior Member
Joined: Jun 2023
Posts: 62
Likes: 21
From: South West of France.
2010 E550(S212), 2006 Chrysler Crossfire (SLK 320 R170 in disguise), 2012 CLS500 (x218)
You don't have a specific ethanol fuel?
We have SP95 E10 that's 10% max all non specified (SP95 and SP98) are 5% max and E85.
Note: measures are made differently for octane rating in here so 98 EU is about 91-93 US.
We have SP95 E10 that's 10% max all non specified (SP95 and SP98) are 5% max and E85.
Note: measures are made differently for octane rating in here so 98 EU is about 91-93 US.
Super Member
Joined: Jan 2021
Posts: 557
Likes: 204
2021 Mercedes GLB250 4Matic
I do not believe US has different % of ethanol. I think it's all 10% as mandated by Federal government. And all gasoline rated by Octane number. We typically only get 3 grades, regular 87, midgrade 89, and premium 93. However on a rare occasion some gas stations have 92 or 94 octane gasoline.
Senior Member
Joined: Jul 2021
Posts: 490
Likes: 176
2021 Glb35 AMG (2013 GLK 350)
Ethanol increases octane and reduces knock and temperature which is good for high compression engines:
Miata has a naturally aspirated engine with lower compression ratios eg 1.6l engine makes 115hp and 1.8l engine makes 128hp.
Miata has a naturally aspirated engine with lower compression ratios eg 1.6l engine makes 115hp and 1.8l engine makes 128hp.
MBWorld Fanatic!
Joined: Sep 2013
Posts: 2,349
Likes: 694
2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
A refining engineer I know says that the government mandate on 10% ethanol in gasoline has been dropped, but EtOH as it’s called, is an excellent inexpensive and low toxicity antiknock additive at about 7%, so it probably will never go away.
I suspect most people on this forum know this: The U.S. stated octane rating is determined by adding the research octane (calculated) and the motor octane (measured) and divided by 2. Some companies state (R+M)/2 on their pumps.
Junior Member
Joined: Jun 2023
Posts: 62
Likes: 21
From: South West of France.
2010 E550(S212), 2006 Chrysler Crossfire (SLK 320 R170 in disguise), 2012 CLS500 (x218)
OK, I now know where the difference is from. in Europe we only use the RON as far as I understand which explains why there is this discrepancy between "octane" ratings between our fuel.
However, from what I could find it's not as much as a calculated vs measured but different test conditions that will set RON (idle and acceleration) and MON (full throttle). At least according to articles such as this one.
Around here, some people go with E85/gasohol without any conversion on some engines and apparently without issue. It's the case with the M112 in the Crossfire (R170 SLK320) and they often go with 50-80% ethanol without any other consideration and from what I read, most of them have no issue other than rough start in the cold and lower MPG.
Edit: For anyone interested, I found this article which sums it up pretty well imo.
However, from what I could find it's not as much as a calculated vs measured but different test conditions that will set RON (idle and acceleration) and MON (full throttle). At least according to articles such as this one.
Around here, some people go with E85/gasohol without any conversion on some engines and apparently without issue. It's the case with the M112 in the Crossfire (R170 SLK320) and they often go with 50-80% ethanol without any other consideration and from what I read, most of them have no issue other than rough start in the cold and lower MPG.
Edit: For anyone interested, I found this article which sums it up pretty well imo.
Last edited by PEagle; Aug 25, 2023 at 02:43 AM. Reason: Added extra link
MBWorld Fanatic!
Joined: Sep 2013
Posts: 2,349
Likes: 694
2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
Thanks for the info. And on the issue of using E85, my old E320 in fact had an M112 engine. So maybe they were all built to handle high ethanol content fuels.
Last edited by Odd Piggy; Aug 25, 2023 at 03:08 AM. Reason: Can’t Type
