We will be storing our '07 MC in our air conditioned garage for 3-4 months this summer in California. The local Mini dealer advised to fill the fuel tank & add some stabilizer. But here in CA they add ethanol to our fuel (about 6% to 10% I think) and an engineer friend tells me that over time gas will separate out from the ethanol which will turn into water in the bottom of the tank, and this will create problems when next running the engine. Does anyone out there know anything about this possibility or have any good advice?

 

I stored my Miata with less then 1/8 tank for 3 months over the winter and after I filled it up it started right up and ran fine. Thats with 8% Ethanol.

 

My MINI used to be a garage queen, now it's driven but not much, but when I used to store it for about a month or so, I'd top off the tank. The problem that I noticed though is that, the car seemed to lack a bit of performance with the older gas, other than that, it ran perfectly!

 

The fuel Stabilizer seems to help with "water" and seperation issues ...
We store motorcycles for 4 months yearly and they fire up and run fine ...

 

Use stabilizer and it should be fine, be sure to put it in and run the engine for a little while so that the treated fuel is in the entire fuel system..

 

I store my cars for 4-5 months a year with full tanks and a little SaBil in the gas. we have 10% ethanol blended gas here. I never have problem when starting up.

 

I also store mine during Mid-Oct to Mid March. I have used Stabil and Gunk Fuel Stab with full tank of 93 Octane gas with good success for the past 3 years. I also start and run the engine for 20 minutes twice a month. If your battery is getting old, use a trickle charge like Battery Tender.