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Mixing diesel amd gasoline

I have a diesel car. With a tank half-full of diesel I mistakenly started to fill up with regular gas. Before I noticed the error I had added about a gallon of regular gas to my tank. In the hope of diluting the regular gas, I filled the tank with diesel and has since refilled it with diesel. Should I have the tank drained (with fuel so expensive I hate to do so) or will the gas just mix harmlessly with the diesel. The tank holds about 20 gallons.

If it’s been running fine, than I’d skip it.

Ditto mountainbike. There should be no problem.

I inadvertently put a half gallon of gas in a seven gallon diesel tractor tank. After filling the rest with diesel, it presented No problems what so ever and the diesel mechanics who work on theses motors say it is well within their tolerance. It’s a problem only if you start making the mistake every fill up.