auto fuel during winter

If you’re going to use MoGas, ONLY use non-ethanol!
That corn juice is really bad for an aircraft engine.

My plane runs great on 91 octane NON ETHANOL. Unfortunately, I have to drive 40 miles round trip to get it. My field does not have fuel, so I fill up a couple of five gallon cans when convenient and top off my tanks as needed.

Only reason considering auto fuel is to help prevent lead fouling in spark plugs. Other than that I have no desire to use auto fuel. Having owned five Bonanzas and one Deb, I never used auto fuel in any of them. With the ERcoupe using less than four/five GPH fuel cost is certainly not an issue!

PS; Wow 75 years!! And I thought I was an old dog. Just turned 80 in October. ERcoupe most likely will be my last flying machine. I am enjoying it as I learn its capabilities! And mine!! Thanks

John:
I don't see your problem - if you have never used auto fuel in a year, certainly any residual by previous owner is gone by now, so why add auto fuel now?
100 LL can handle long term storage. I once found a drum of 100LL in my hangar that I had forgotten about and had a Bonanza wit high compression big bore Continental, so I called Ben Visser, the retired Shell Guru, and he said no problem with long storage for the 100LL. So when I ran it in the BO with 6cyl engine monitor, I didn't see any difference in EGTs & CHTs with the fresh.
When I don't to get to fly often and I use auto and 100LL mix, I just drain all the fuel and burn in an old truck and refuel with some 100LL in each tank and system.\FWIW

Happy Holidays, also

PS Compliment you on you additives. I've only been flying 75 years and an IA.

I have a 1948 415E with C-85 egine (2250 SMOH).  I usually fly once a week until winter time.  It has the STC for auto fuel.  I have never used auto fuel in the year I've owned it.  I'm considering mixing it with avgas.  However, because I fly less often during winter months,  I'm concerned about problems with auto fuel just sitting for long periods of time.   For example, the effect auto fuel has on carburetor, hoses, gaskets, etc while the engine is not being run for long periods of time.  I do add some  MMO and Avblend (6-8 oz.) during oil changes which just occurred during the Coupe's annual this month.  Comments and recommendations would be appreciated.  Thanks

Happy Holidays!!