per manufacturer recommendation, have always run 91 octane, non-ethanol in my '98..always runs like a champ...suddenly here in Central NY, ethanol free 91 octane is no longer available...guessing for economic/pricing reasons...petroleum engineers, feel free to advise...so my fuel choices now are...run 90 octane ethanol free...or...run 91/93 octane with 10% ethanol...which and why?...can get 100 race gas, but at $8 a gallon, a bit hard on my wallet..haha...

many thanks to all who reply...

Tom

What makes ethanol attractive is its ability to increase the octane level. Your car will run nicely with 10% ethanol, so long as it is a daily driver. If you car sits for long periods of time with high humidity, the tank will collect water.

I use 10% in my car in the summer, then switch to 100% gasoline before winter storage. I typically do not drive the 1995 850 from December to April, when the salt is off the road. No snow tires needed!

I agree with using ethanol free for the small engines. They typically do not use a lot of gas, about 5 gallons/summer.
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Keeping it running is better than buying new

many thanks to you both...my '98 is my daily driver, so I guess I will be okay with the occasional tank of corn laden fuel..for now..winter time is loooong and cold here in CNY, so I'll be fueling with the ethanol free at that point..and I NEVER run ethanol gas in my small engine/outboard engine et al..eats the seals up something fierce...more than willing to seek out and pay for the highest octane non-ethanol free fuel I can find...

"more than willing to seek out and pay for the highest octane non-ethanol free fuel I can find..."

I worked in a small power equipment repair shop for a few years a few years ago.
Bottom line and the word from our largest manufacturer (Husqvarna) representatives was "always use stabilizer and 89 octane in small engines is what we'd use."

So take that for what it's worth.

until recently, ALWAYS ran 91 non-ethanol in all my small engine/outboards...have an airport nearby...maybe av gas in the offing..

Your engines are engineered to use unleaded gasoline. AVgas is 100 octane with lead, and quite expensive. Most airports will not sell any gas that is not used in airplane engines, there are laws...

Older cars, pre ethanol, had rubber parts in the fuel delivery system. The unfortunate result of using ethanol was rubber was being dissolved by the ethanol. Because ethanol replaced the lead additive, one needed to replace the valves which were no longer being coated with lead, the 'soft' valves were wearing away rapidly.

Most of the engines affected by ethanol were carburetor based, with all of the rubber seals in the carb.

Your best bet is to write to your esteemed representatives, state and federal, and let them know that 15% ethanol will destroy car engines and result in lower MPG.
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Keeping it running is better than buying new

Your best bet is to write to your esteemed representatives, state and federal, and let them know that 15% ethanol will destroy car engines and result in lower MPG.


A fabulous idea, but unfortunately the mid-west corn lobby has more drag
in Washington, and politicians need the threat of lynch mobs to change their
seedy behavior.

^^^
Sad, but true.

Unfortunately, I don't believe any politician gives a rat's a$$ about reducing the ethanol mandate.

within a twenty mile drive of me is a garage that also doubles in fuel sales, with various products from Sunoco, in higher octanes, both leaded and unleaded..waiting for an email response...

I'm not a petroleum engineer.

E10 will not be a problem in a 1998 car.
Expect an approximate 10%-15% drop in fuel mileage when using E10.

Given your choices, if it was me, I'd use 90 octane ethanol free gasoline.

On a side note, avoid ethanol blended fuel in small power equipment if possible. If not possible be sure to use fuel stabilizer. Heck, regardless, you should use a fuel stabilizer.