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

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.

It can't possibly explain the fuel gauge not working. What's not entirely clear from your first post is whether the engine is actually cranking but not starting, or is it not even cranking?
 
From what you said in the opening post it ran the ten miles home, then ran again when you used it later that evening then was totally dead when you tried to start it the next morning right?
 
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 ****)

3dr Novas have box arches though, which makes them cool! :D
 
Normally this would be ok because it's only a tiny amount. But I guess some modern cars go crazy and shut down when they detect ANYTHING bad with the fuel.
 
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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.

I don't believe at 06 they had that on fuel fillers though I may be wrong,

You will find a company online that will come to you and flush it for you
 
I always thought petrol in a diesel was really bad.

But diesel (small amount) in a petrol was not so bad.

I personally dont think the disel and petrol would seperate. I would have thought the petrol would act like a solvent and water down or thin out the disel. Could understand it being a bit smoky.

2 litres in a 50 lite tank isn't much. A quick look at the spark plugs might tell you if the issue is the diesel.. they might be a bit on the wet side/ too wet to get a spark.
 
I don't believe at 06 they had that on fuel fillers though I may be wrong,

You will find a company online that will come to you and flush it for you

They've had it since the mid 90s at least. You have to really ram a diesel nozzle into an unleaded car to get it to fit.
 
From what you said in the opening post it ran the ten miles home, then ran again when you used it later that evening then was totally dead when you tried to start it the next morning right?

Almost right. The electrics turned on in the morning but the engine didn't kick in. Then every time I turned it off and on again there was less and less juice until now, when I go to start it, I get nothing.
 
It can't possibly explain the fuel gauge not working. What's not entirely clear from your first post is whether the engine is actually cranking but not starting, or is it not even cranking?

Not even cranking. Almost as if a sensor was detecting no petrol and so not even trying to start the engine.
 
Yep definitely sounds electrical, it'll no longer be even trying to crank because you'll have totally flattened the battery with repeated tries. Starting up an engine or attempting to takes a lot out of a battery.

I don't know about cars but on bikes when the battery/charging system goes funny then it can cause strange instrument readings such as your empty fuel gauge.
 
The prius uses a small auxiliary battery to turn on the car electrics then engage the large main battery that in turn switches on the engine if i recall correctly from when I had mine. Did you get the red large triangle of death on startup as the battery was getting lower? When the 12v aux battery on a prius gets low it causes all sorts of insane warnings and electical gremlins eg. mine wouldn't lock then would lock and then did and sound the alarm randomly. Try getting the 12v battery charged or replaced but it does need a diff battery than normal due to the breather tube being needed.
 
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The prius uses a small auxiliary battery to turn on the car electrics then engage the large main battery that in turn switches on the engine if i recall correctly from when I had mine. Did you get the red large triangle of death on startup as the battery was getting lower? When the 12v aux battery on a prius gets low it causes all sorts of insane warnings and electical gremlins eg. mine wouldn't lock then would lock and then did and sound the alarm randomly. Try getting the 12v battery charged or replaced but it does need a diff battery than normal due to the breather tube being needed.

It's hard to remember what the dash was showing because I didn't get a good look before the car went properly dead but there were definitely warning lights. I think the big red triangle and the red circle with the exclamation mark inside.

So maybe it's a case of a failed battery rather than the misfueling? Might actually save me some money. I am with the RAC so I will call them out in the morning (didn't have a chance today). Are they likely to be able to charge the battery for me? I don't even know if that's a 'fix' or if I'll still need to buy a new battery.
 
It's hard to remember what the dash was showing because I didn't get a good look before the car went properly dead but there were definitely warning lights. I think the big red triangle and the red circle with the exclamation mark inside.

So maybe it's a case of a failed battery rather than the misfueling? Might actually save me some money. I am with the RAC so I will call them out in the morning (didn't have a chance today). Are they likely to be able to charge the battery for me? I don't even know if that's a 'fix' or if I'll still need to buy a new battery.

Surely there must be some protection to stop the 12v battery going low, i.e run the engine to charge it? Like stop/start wont kick in if the 12v battery is low.

The RAC will try and jump it and then will tell you to take it for a drive. Thats if its the issue...
 
Update. Turns out it was a dodgy 12v battery, not anything to do with the diesel mishap. RAC came out and tested the battery and it read 6v instead of 12 :( The guy charged me £80 to replace it there and then and now it drives like a dream (or, at least, as well as a Prius can :D). I probably could have got it done cheaper at my mechanic's but that would have taken half a day would have required putting the car on a flatbed and all that faffing.
 
That's actually a good price for the Prius 12v its about £100 quid fitted at Toyota fixed price. Glad you found it was the 12v it usually is with the Prius. Did you make sure that he put the breather tube on the battery?
 
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