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Flex fuel in a non-flex car

I inadvertantly filled my non-flex Chevy Tahoe with 10% Ethanol fuel. The check engine light came on as soon as I drove away. Do i need to drain the tank, or what?

Every modern (~1995 or later) car on the road should be able to use 10% Ethanol fuel. You only need a flex fuel vehicle to use E85 (85% Ethanol, or concentrations above 10%). The check engine light is probably the fuel cap or something unrelated.

Check your gas cap and make sure it is securely fastened. If the CEL doesn’t go away, take the car to an auto parts store. Many of them will read your CEL trouble codes for free. Post the alphanumeric code (not the diagnosis) here and we might be able to help.

If your vehicle was made after 1995, E10 shouldn’t harm your Tahoe.

Are you sure it was E10 and not E85? Just about all gas is now E10.

We have all been burning E-10 for several years now…That did not make your CEL come on.

“Flex-Fuel” vehicles can burn E-85, a completely different animal…

Yes make sure you are talking E-10 and not E-85. We had a guy at work that used E-85 in a company car twice and both times they had to drain the system to get it out and reset the computer again.

There should be no problem with E-10 but E-85 is a different animal. Your vehicle must be a flex fuel one in order to burn the 85% ethanol and 15% gasoline mix.