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What kind of car engine damage could be caused by gasoline mixed with diesel?

HI! On an out of state trip, our gas tank was near empty when we filled it up. We made it home fine. The next day, the car shuttered, died, smoked, etc…my first thought - BAD GAS! Mechanic said = Diesel had been in the gas tank.

Called convenience store where we filled up - they admitted their fuel tanker delivery person accidentally mixed diesel into the gasoline tank.

Mechanic Bill = $600+ Convenience store (or tanker delivery company) sent us a check! (I couldn’t believe it - I thought FOR SURE they would deny deny deny any wrongdoing, etc…

HOWEVER, my car still doesn’t seem the same. It has a weird odor. COULD THERE BE ANY FURTHER damage, yet undetected due to this situation? Could the engine be damaged beyond repair, etc… THANKS! :slight_smile: J-Cat in Kansas.

Did your mechanic give you any idea what percentage of the fuel was diesel? What did your mechanic do, other than presumably getting the bad gas out of the tank and the fuel system?

I’m thinking that engine damage isn’t likely here, although am I wondering if anything bad could have happened to the catalytic converter.

It might not hurt to run some Techron through the fuel system for your next few fill-ups.

How does the car “seem” now that isn’t right? How many miles since the problem was handled? Usually, the damage that diesel causes is from detonation/pinging in the combustion chamber that cracks pistons, etc. If the ratio of diesel to gasoline was not great enough to cause the pinging I wouldn’t think that any damage was done. What repairs did your mechanic make?

I have the same questions as the other two. I’m also not surprised that the convenience store sent you a check - the fuel supplier who screwed up is on the hook for this, so whatever they pay you, they’ll turn around and get out of him.

I know QT, which abounds in KS, has a fuel guarantee. If bad fuel causes a problem with your car, they will pay. It stems from a time SEVERAL years ago when they had a BIG fuel contamination issue. Their paying may be due to an agreement they have with their fuel supplier(s), which indeed caused the problem.

Back in the olden days, many farm tractors were run on what they referred to as petroleum distillate, or distillate for short. It was very close to kerosene or diesel. What the farmers did was start their tractors on gasoline, and run them until they were warmed up. Then they switched over to the cheaper distillate. We had a very old plow tractor when I was a kid that still had the little gasoline tank and valve, but I don’t think my dad ever tried running it on anything other than gas. This is why your car made it home OK. The engine ran fine as long as it was warm, but would not run at all well when it was cool.

I’d be surprised if the diesel mix really hurt anything, but you might want to get your favorite shop to take a second look. After all, if the supplier paid up once, they should pay again if you still have a problem.

How many miles did you drive on the mixed fuel? If you did not HEAR your engine complaining (knocking / pinging) then it’s unlikely any mechanical damage was done…The only real problem would be if you tried full-throttle acceleration…You would certainly have heard the engine complain then…

Another unknown is the actual percentage of diesel fuel in the “blend” you purchased…How much diesel did the driver dump in the storage tank and how much gasoline was in in the tank when the fuel was delivered…

Hopefully, you can just drain your gas tank, refill with gasoline, and drive on, $600 to the good…