what would happen if i put diesel in an unleaded car.?

Answer 1

Happened to me. The fuel truck mistakenly pumped diesel into the unleaded tank. After pumping my fuel, the engine sputtered then died. The tank had to be pulled and flushed, fuel filter and lines flushed. Plugs had to be replaced, and injectors. Fuel pump had to be serviced also. Cost was over $600, but the bill was paid by the station.

Answer 2

If it's only a little bit, fill it up with unleaded and it should be fine, might 'pink' a little

If it's a lot: oh sh1t, call the AA, RAC, whoever - they'll come and suck it out. If you've turned the engine over with that gunk in it, the car's entire system will need to be flushed.

FFS, don't try starting the engine.

I'd get some professional advice first.

BTW: when the RAC, etc suck all the gunk out of cars where people have put in the wrong fuel, did you know they sell it to the army to use in tanks? Tanks can run on almost anything, so a mix of diesel and petrol is fine. So there you go.

Answer 3

Not a good idea. I have put unleaded into a diesel, I filled the whole tank before I realised...... what can I say... I was having a bad week... I had to call the breakdown people to take the car to the garage and they had to drain the tank. It cost me about 150 Euros, plus the full tank of petrol.

Answer 4

It would run, badly, very smokey.
if you only put a couple of liters in then fill it up with unleaded and dilute it, the performance would be down untill all the diesel is used up.
If you have compleatly filled it up with diesel, then syphon out the diesel and fill it with unleaded.
Diesel in a petrol = Not a good idea, smokey but not much harm done.
Petrol in a diesel = Bad idea, petrol runs a lot hotter than diesel and will really mess up your engine.

Answer 5

Most of the answers here are on the ball. I have done the opposite - petrol into my diesel. RAC will not pump it out - they tow you to a garage that charges £180 or to your home where your local garage does it for £30 ( I chose the latter). Damage to engine - nil. Diesel in a petrol - happened to my friend - drove only a few yards - no damage done - but any further and your catalyst is dead and you will need your injectors cleaning out .

Answer 6

Well you might make it from the petrol pump to the road then your car would cut out . You then will need to call a mechanic, the car will have to be towed to a garage all the diesel drained out, the fuel system cleaned and then refilled with petrol. Very bad for your car don't do it!

Answer 7

Unleaded gasoline ignites at a different temperature than diesel, and I know that instead of a spark, diesel needs total combustion ...something the gasoline driven cars do not have. You would probably ruin your fuel system.

Answer 8

The engine will probably die if there is no gas in the tank. If you are talking about a very small amount mixed with the gas, it will just smoke until the diesel runs out.

Answer 9

It will run for a short time on the existing petrol in the carb and fuel lines, but start pinking and eventually give up the ghost with black fumes coming out of the exhaust!!

Answer 10

The engine would misfire, then stop, until you cleared out the tank and refilled it with petrol.


This error is something that has occurred many times in the past years, and whilst it did not cause any damage to the engine, I do wonder if the current range of "engine management" systems might be damaged.