FAIRMONT - Fairmont was one of 21 communities to receive a bad batch gasoline over the weekend from a Mankato distributor.
Kwik Trip spokesman John McHugh said the Fairmont store got a shipment of unleaded gasoline with a higher-than-usual ethanol blend - how high he wasn't saying.
Kwik Trip customers who bought gas between Friday and Monday should not have problems with their cars, but if they do it should be mild, McHugh said.
"Let's say you have an empty tank and you fill it up," he said. "You might get a check engine light ... you might get a pinging or a knocking."
Exactly how much ethanol each customer got depends on how many gallons were in the tank when the mismixed fuel was added.
If customers notice problems with their vehicles, McHugh said to come into the store and fill out a form, which will be forwarded to Magellan Midstream Partners, whose Mankato plant shipped the fuel.
Magellan pumped the mismixed fuel out of the local tanks, washed them out and put in the correctly combined gas for most of the grade levels.
However, a local Kwik Trip employee who asked not to be named said Wednesday that the mid-grade gas still needed to be pumped out. She didn't know exactly when the process would be resolved.
Kwik Trip wasn't the only station affected by the bad gas, but a comprehensive list of places the gas was sent has not been released.
Ethanol blends are set at 10 percent in Minnesota for general use, although some vehicles can take much higher doses of the corn-based fuel.
Flex-fuel vehicles are built to take up to 85 percent ethanol mixed into the fuel - called E85.
Corn growers associations are pushing to have the standard blend increased in standard fuels to higher levels - specifically E20.
Other area communities that received the mismixed batch of fuel are Winnebago and Blue Earth.