10% Ethanol Premium Gas vs No Ethanol Gas

[mnx5er]

In my neighborhood there is one gas station that sells premium for 2.97 with 10% ethanol. The other station has ethanol free premium for 3.31. Both are listed as top tier.

I’ve read that E10 drops gas mileage 3%, so that hardly justifies the price.

But - is it worth the extra $ for the engine in the long-term? Never really thought about it until I was staring a the ethanol free pump tonight while in my X.

[sj22]

Depends on how aggressively you drive. If you are below 3k rpm and dont drive more than 6-7k miles a year, then 10% ethanol is probably ok.

[mnx5er]

Originally Posted by sahiljain22

Depends on how aggressively you drive. If you are below 3k rpm and dont drive more than 6-7k miles a year, then 10% ethanol is probably ok.

Well, I’m 0 for 2 on that. 16K a year and I drive it like a BMW. In Minnesota ethanol is everywhere.

[F15GorDe]

The dealer WILL pull a fuel sample from the tank of any warranty related issues where fuel could be a factor. BMW denies claims where ethanol content exceeds 10%.

[perry8912]

Personally, I’d choose the one without ethanol.

[Habs11]

Everything in my area has 10% ethanol except one local mom and pop chain has ethanol free premium. I don't know the science behind it but I've heard ethanol is worse for small motors (weed eater, chain saw, mower) than auto motors.... is that true?

[DETSGTSTARSKY]

Originally Posted by mnx5er

In my neighborhood there is one gas station that sells premium for 2.97 with 10% ethanol. The other station has ethanol free premium for 3.31. Both are listed as top tier.

I’ve read that E10 drops gas mileage 3%, so that hardly justifies the price.

But - is it worth the extra $ for the engine in the long-term? Never really thought about it until I was staring a the ethanol free pump tonight while in my X.

Check out the local Kwik Trip stations that can have no ethanol premium. Or look on pure-gas.org for a nationwide list of stations when traveling. Ethanol is really not what you want in the fuel system.

[mnx5er]

Originally Posted by DETSGTSTARSKY

Check out the local Kwik Trip stations that can have no ethanol premium. Or look on pure-gas.org for a nationwide list of stations when traveling. Ethanol is really not what you want in the fuel system.

Kwik Trip is where I quoted the ethanol free price from. About a mile from my house. Always avoided it since I was fine with the ethanol mix from Holiday or Costco.

Interesting thread. Owned BMWs for a LONG time and never considered this.

[Maverik259]

Originally Posted by Habs11

Everything in my area has 10% ethanol except one local mom and pop chain has ethanol free premium. I don't know the science behind it but I've heard ethanol is worse for small motors (weed eater, chain saw, mower) than auto motors.... is that true?

Ethanol attracts water and doesn't burn the same as gas. Water in an engine is always bad and the alcohol in ethanol breaks down the seals much quicker. Pure gas can give you anywhere from 2-3mpg more. So it's up to you. Can't hurt to give it a try once or twice and see what kind of mpg you're getting. And if it's worth the cost. The long term damage is much more difficult to quantify unfortunately.

[pits200]

Lots of misinformation on here about e85. Here is some insight.

All lines are rated for ethanol, no worries about running it.

Ethanol will help your engine run cooler on egts due to its cooling properties especially since our engines are direct inject.

Ethanol is the equivalent of 105 octane gas

Yes you will get slightly less mpg as ethanol has about 30% lower btus than gasoline. Conversely, diesel has much higher btus than gasoline and why you get better gas mileage.

Ethanol can retain water but with such a small blend it won't matter and it would take a few months of the car sitting for this to happen.

If you ever tune a car, you can run much leaner with ethanol which helps with torque and it is much more knock resistant

Unless you care about the small decrease in gas mileage from an e10 blend, don't go out of your way to get no ethanol gas. In all honesty, your car probably would run better with an ethanol blend especially in the summer.

I had a 335 running straight e85 for 2 years, best mod next to upgraded turbos