Accidentally Pumped Diesel into a Petrol Car? What Can You Do?
We may think it is impossible. But if you are tired or distracted, you may grab the wrong pump and watch as the fuel counter starts ticking. Once you realise you accidentally pumped diesel into your petrol car, you can take action to save your car.
Petrol vs Diesel
But what exactly is the difference between petrol and diesel? Turns out, quite a bit.
| Petrol | Diesel |
|---|---|
| The unique blend of petrol and chemicals prevent self-ignition | Diesel can ignite by itself with hot air that is highly compressed |
| Spark plugs ignite a gas and petrol mix to get the engine running | Diesel engines do not have spark plugs |
| Low compression ratio | Thicker than petrol |
| Cleaner burning | Better gas mileage |
These differences result in very different engines with different pros and cons.
What Happens if You Pump Diesel in a Petrol Car?
As diesel is thicker and more viscous than petrol, it can stick to and jam a petrol engine’s fuel injectors, lines, and filters. Petrol engines also do not create enough heat and pressure to ignite the diesel which causes serious cylinder issues as the engine misfires. Smoke emitting from the exhaust pipe is a telltale sign of this occurring.
Overall, your car may initially start but the performance will start to slip until it stops running altogether and may never start up again. Although catching the mistake early can result in an expensive repair bill, trying to fix it on your own may cost more.
How to Remove Diesel from a Petrol Tank
It all depends on when you realised you pumped diesel. If you are somehow driving, stop immediately!
- Low amount of diesel
A low amount of diesel in the petrol tank is usually not harmful, it just has to be caught early on in the pumping process. You can pump petrol in to correct the mistake.
- High amount of diesel
If you accidentally pumped diesel into most of your tank, you have two choices. In either case, you have to immediately fix the problem as serious damage can occur if the diesel sits for too long.
The first option is to have the car towed and remove the diesel with a siphon pump, replacing it with petrol. From there, you have to let the diesel naturally flush out.
The second option is to get a professional mechanic to flush the entire fuel system which we recommend.
Having accidentally pumped diesel into a petrol car can be a headache. However, you can still save your car. Be mindful when you pump!
So, how often do you pump and how much? Do let us know below!
