2004 Toyota Sienna - Wrong fuel

I filled up my tank with gasoline in the morning. That evening I drove a little over 100 miles and the car suddenly stopped dead. The warning lights all came on. When I tried to restart it it sounded like it was starting but immediately died. Toyota tells me that I had diesel fuel in the tank. Is this possible?

Possible ? Yes it is . This Forum gets about one post a week from someone who put deisel fuel in a gas vehicle.


Yah, but I drove non stop over 100 miles with no issues before the car died. Also, the diesel nozzle is incompatible with a gasoline car. It’s too big in diameter to fit in the fuel hole.

I agree but I have found in my area the diesel nozzle will fit into a gas tank at the BP stations.

I’m sure I didn’t use the diesel nozzle, but if I did, how does a gas car with diesel in the tank run non stop over a hundred miles with no issues? Don’t you think that’s strange?

That has not stopped many of the people who do this .

Sorry, but that doesn’t answer my last question about how the car ran over a hundred miles non stop with no issues don’t you think that’s strange?

With over a hundred miles before it quit I think you would have noticed a difference in the way it was running plus smoke out of the tailpipe.

Yes! That’s what I’m saying. It was running perfectly, and I didn’t see any smoke but it was dark (although I did drive at least a couple of miles after I tanked up that morning). From what I’ve read I should only have been able to go a few miles before it died, or at least exhibited obvious problems.

I think that maybe Toyota does not know what the problem is with your car and is trying to tell you to take it somewhere else. Most cars will not go very far without very far before problems show up.


It wouldn’t run that long on diesel fuel. Why not syphon some of the contents of your tank and have it analyzed by an independent lab.

When was the last time the timing belt was changed?

Diesel fuel is heavier than gasoline. It would sink to the bottom of the tank and be drawn in to the pump before the lighter gasoline.

So… you didn’t say how much gas was in the car when you filled up. 1/8th tank? 1/2 tank?

If it was near empty, I doubt there is any way you could go 100 miles before the truck stopped running. If it was 1/2 full, I think you could go 100 miles before the diesel caused it to stop.

As for what actually happened; YOU might have put diesel in, the stations tank might have HAD diesel in it, OR Toyota made an error in their assessment… there is really no way for us to know and little way for you to prove someone else is at fault.

In any event, you are paying to fix this at an expensive Toyota dealer, for a 17 year old car.

Well, the Geico insurance guy is going over there on Monday and he’s gonna have them show him a sample of what’s in the tank. I don’t know, maybe I’m naive but I find it hard to believe that Toyota would make this up.

wait, what? I find it hard to believe a insurance agent is going to go to the dealer for a fuel related problem. especially on a 17 year old car.

I changed it seven years ago at 90,000 miles. It’s got a little under 150,000 now. I think if it was the timing belt thy would’ve told me.

Well, they’re covering it. I just have to pay my deductible.

Anyone is capable of making anything up to try and scr*w you.

The majority of posts we get here where diesel was pumped into the tank of a gasoline engine vehicle, the driver doesn’t get more than a few miles from the gas stations before it conks out. Sometimes just a few blocks. Given what you say, one possibility is that the gas pump you used was possibly used for diesel before, and the station has just switched it to gasoline, and a little diesel was still in the lines. That could explain how you were able to drive 100 miles; i.e. the diesel was a very dilute mixture. Even a dilute mixture will eventually cause problems with the car’s O2 sensor readings and possibly damage the fuel injectors and the catalytic converter.

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Thanks, that’s probably the most sensible answer that I’ve gotten here.