I put a small amount of diesel in my Prius and now it won't start

kissenger

kissenger

kissenger

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So yesterday when I was filling up I foolishly put a small amount of diesel in my '06 Prius (the meter got to around £2.50 before I realised). I thought I would be okay if I just filled up the rest of the tank with petrol (which is what I did), but I've just went to start it and it's dead.

It did start at first, but I think it was running on the residual battery charge because the engine didn't kick in and the fuel gauge showed empty. I drove it around 10 miles home from where I filled up and then used it again later that evening.

What should my next moves be? Is draining the tank and refilling likely to work or will it have caused more severe damage? I did read somewhere online that diesel in the tank can cause the gauges to go haywire so maybe if I can get it running and top up with a bit more petrol it will eventually 'flush' out the diesel?
 
I thought the nozzle on the Diesel pumps were bigger meaning you couldn't fill up a petrol with a diesel due to the diameter...I think its going to be a flush job...
 
There's no reason 2ish liters of diesel in a full tank of petrol would completely kill it.
 
First of all, you can't fill a petrol car with diesel by mistake. Diesel nozzles are bigger than the filler neck on petrol cars. Also, there is a plate under the neck to prevent any intrusion but the small petrol nozzle, which was designed to prevent drivers from putting leaded(big nozzle too) petrol in the first place. If you happen to do that somehow, you wont damage the engine even if you try to start it.

Diesel is heavier than the gasoline, and much more "oily". It needs pressure to be ignited and does not evaporate as gasoline do. What happens after putting diesel on a tank is, diesel sank and injectors feed the engine a load of diesel. When you try to ignite the engine, spark plugs won't be able to fire the diesel and the engine won't start.

To fix the issue, draining the tank and filling it again with gasoline ,cleaning the injectors and finally cranking the engine to throw up the unwanted diesel would suffice. Some may want to change the fuel filter to be on the safe side but it is not a must.
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https://www.quora.com/Which-is-wors...-petrol-car-or-petrol-in-a-diesel-car?share=1
 
Diesel is heavier than petrol though is it not? So if he put it in first, the fuel mixture it sucked out initially might have had fairly high diesel content?
 
That's a fair point especially if it ran on electric for a while and it had time to separate out I suppose unlike a normal car where it would still be churned up after filling.
 
tom_e said:
That's a fair point especially if it ran on electric for a while and it had time to separate out I suppose unlike a normal car where it would still be churned up after filling.
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My car rarely if ever runs on just battery. Usually only just when I'm below 10mph. After that the petrol engine kicks in.
 
snips86x said:
I thought the nozzle on the Diesel pumps were bigger meaning you couldn't fill up a petrol with a diesel due to the diameter...I think its going to be a flush job...
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I don't know if it's something to do with my car, but I didn't have any trouble getting the diesel nozzle to fit.
 
Seems very unlikely that 2 litres of diesel in a full tank of petrol would cause this. Sounds like it's just an unlucky coincidence, especially as the fuel gauge is reading empty.

tom_e said:
That's a fair point especially if it ran on electric for a while and it had time to separate out I suppose unlike a normal car where it would still be churned up after filling.
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Diesel and petrol mix perfectly well together and don't easily separate out. If all the different length hydrocarbon chains naturally separated, oil companies wouldn't have to use fractional distillation columns to separate them out. They'd just need to pull the pipe out of the ground a bit to get petrol, and push it down further to get diesel :D
 
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I wouldn't have thought a small amount would have done any harm. Many years ago my Dad had a customers diesel in that they had accidentally filled with petrol, he drained the tank and we used it in my old Nova, it didn't seem to mind at all. (I'm still ashamed that I owned a Nova, what a piece of ****)
 
I wouldn't have thought that 2 litres of diesel in 45litres of petrol would cause any issues. Bit strange how you could get the diesel nozzle pump in a petrol filler.
 
Gaygle said:
I wouldn't have thought that 2 litres of diesel in 45litres of petrol would cause any issues. Bit strange how you could get the diesel nozzle pump in a petrol filler.
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This is what I keep hearing from everyone I've asked, but it is one hell of a coincidence for something else to go catastrophically wrong one day after misfueling.
 
Petrol and diesel do mix, so it's not like water and oil where they separate. It does seem very unlikely that such a small amount of diesel would do any harm that is for sure.
 
Nick1881 said:
I wouldn't have thought a small amount would have done any harm. Many years ago my Dad had a customers diesel in that they had accidentally filled with petrol, he drained the tank and we used it in my old Nova, it didn't seem to mind at all. (I'm still ashamed that I owned a Nova, what a piece of ****)
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HAHA!!! I had one too, was my first car :eek:
 
I ended up putting a gallon in a diesel once as it was in a petrol can and I had a cold.

Other than being noticeably down on power and sluggish, it was completely fine after filling up with petrol again.
 
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