I have a beautiful 2012 Mini Clubman which I love! She has just under 7K miles and runs like a champion. 2 weeks ago, after buying some gas at my nearby BP station, my check engine light came on after driving approx. 20 miles. Since car was new and under warranty, I was diligent and called the dealer. First they told me to retighten the gas cap and see if the check engine light went out.
After a few days, check engine light stayed on, so I was asked to bring car in to service. To make a long story short, the dealer found a misfire situation, first replaced pressure sensor and hot air film sensor before they checked the fuel and found 75% alcohol in my fuel! They told me I put E85 into tank.

It turns out that my BP station in Wisconsin has E85 pumps right next to regular-mid-grade and premium pumps. It was early in morning rushing to work and I accidentally put in E85 instead of premium. (Beware people, look at what is on the gas pump before you put fuel in!.)

Now the diagnostics: The E85 was in the tank for approx 320 miles before we found this problem. During this time, I never noticed any misfire, stalling, issues with cold starting or anything. It was really confusing me. On the last day before I took car to dealer, I noticed a slight decrease, approx 1 mpg in my average fuel consumption.

The dealer is suggesting various options, one being to just leave the car alone, fill with new gas and reset computer.

Any experts here whom could tell me if one tank of E85 can do harm to a Mini Clubman? Remember its a Justa.
Could one tank of E85 affect warranty?

Kindest Regards

Cool Designer

 

I am surprised you only noted 1mpg less because E85 burns faster than regular gas. Ummm normally the fuelpump, fuel injectors, and spark doesn't like E85 and are normally the things that give the first problems after that it is normally the rubber lines that go. Hmmm keep fueling up with premium and see what happens.

 

Not much you can do unless you want to randommly start swapping parts that MIGHT have been harmed....
Put regular premium fuel in, and see how it works.....
Bet any good dealer would record the fuel finding.....
Then see how it runs....
The warrenty might not be voided, but i bet if something odd turns up, they can say it was the e85, and MAYBE it was....

 

There was a thread somewhere on E85 fuel. I believe it was a Mynes tuned car that had a specific tune for that fuel. If my memory serves me correct the E85 requires larger injectors and a special tune so that you do not run lean. If tuned properly it will give you more power. I do not recall a problem with melting of fuel lines. How this will effect your MINI with stock tune on a Justa I am not sure.
Steve

 

E85 requires different types of plastic in the fuel system than normal gasoline.