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Mixing Diesel with Gasoline

I have heard that mixing a cup of low octane gasoline with a 20 gallon tank of diesel will help keep your injectors clean, and at the same time give a slight energy boost to the fuel in the tank. All without causing any harm to the engine. This sounds like it could actually work. Do you think that it may actually be feasible?


Diesel Ted

Feasible? Sure. Beneficial? I can’t see why. Diesel fuel is specifically formulated for diesels, if all it took was ‘adding a cup of gas’ to create a superior fuel, that could (literally) be done with the push of a button in the refinery.

Also, diesel fuel contains more energy/gallon than gasoline.

Don’t do it.

What your diesel needs to keep the injectors clean is already in diesel fuel and yes, we own a diesel; have owned one or another since 1981 except for a couple of years in the mid 1980s. A cup of gasoline in 20 gallons will neither help nor hurt your diesel. One of our older VW diesels was permitted, according to the owner’s manual, as much as 1/3 gasoline mixed with diesel fuel to eliminate jelling of No. 2 diesel fuel in extremely cold weather. That is no longer permitted in modern diesels. I have not heard of diesel injectors getting dirty but they can wear out.

I remember in November 1989,we had so much trouble with Diesels stalling,one solution was to mix 10% Kerosine with the fuel to combat gelling,was never any mention of using gasoline-However I think Mercedes used to recommend adding a certain percentage of Hi-test to diesel in the winter.Little merit to it now,Diesel has already lost enough lubricity,just dont do it-Kevin

I don’t think this is a good idea @DieselTed. I’m no diesel expert, but gasoline is such a powerful solvent, I’d be worried it might damage something – like the seals – in the fuel injector pump. The folks who designed the fuel injector pump designed it to handle diesel, not gasoline. I’d suggest not trying this unless you have experience from someone who has tried it, and on the same engine with the same injection pump you have.

When I inadvertently dumped gasoline into my tractor, about a quart or two, the mechanics at the tractor shop did not seem to feel it was a problem for that little amount. But, just because it isn’t a problem does not mean you should do it when additives specifically made for diesels will actually do the job. Unless a certified diesel mechanic posts a reply, just don’t do it.