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What happens if you pour the wrong fuel into your car?

Who’s “crazy” enough to pour the wrong fuel into their car - you might ask. What if we told you that, based on the information received from professional car services throughout Serbia, more than 150.000 people per year go through this unpleasant experience? Would you want to find out more about what to do in a situation like that? Let us deal with the subject in the article that follows.

What happens if you pour the wrong fuel into your car?


The Difference between Gasoline and Diesel

In order to understand why it matters what kind of fuel we pour into our cars, you need to get acquainted with the differences between gasoline and diesel fuel. Technologically speaking, these 2 fuels share an identical goal, but their ways of achieving it are different.

Gasoline requires a fine sparse mixture, as well as a spark, which initiates the burning process. It doesn’t stand too much pressure (compression). Unlike gasoline, diesel needs a high level of compression in order to self-ignite, without the use of a spark. It means that, if you light up a match and toss it in a tank filled with diesel fuel, nothing’s going to happen (which in no way, shape or form means you should do it - on the contrary) because a match on fire doesn’t have the capacity to warm up the fuel enough to cause its burning. Of course, in the case of gasoline, this kind of scenario can be devastating, so make sure you don’t play with fire (literally speaking) while in proximity to gasoline fuel.

The Difference between Gasoline and Diesel


Pouring Gasoline into a Diesel Car

Gasoline can do more damage to a diesel car than the other way around. Even small amounts of gasoline are capable of washing down the thin film, whose function is to lubricate the diesel fuel injection pump. The problem occurs due to the fact that gasoline’s lubricating qualities are not equal to those of diesel.

What’s more is that gasoline is more flammable than diesel, which means that, in case it reaches a diesel car’s tank, it will detonate faster, thus causing misfires, sputtering, knocking, reduced engine power and potentially permanent engine damage.

Have in mind that modern Clean Diesel and Common Rail diesel cars are far more sensitive to gasoline than its predecessors and that, as a consequence of that, the smallest amount of gasoline in their tanks can produce damage to the emission system controls. Moreover, gasoline’s burning within any diesel engine will almost certainly lead to unrepairable engine damage.

Pouring Diesel into a Gasoline Car

It’s more difficult to pour diesel into a gasoline car than the other way around. Why? Because the diesel fuel gun doesn’t match gasoline cars’ tank opening, which serves as a certain form of protection, but unfortunately, it’s not an obstacle one cannot circumvent (this applies to modern diesel cars, seeing it as it is not the case with the older models).

Even a mixture containing only 5% of diesel can cause expensive damage to a gasoline engine and its catalytic converter, assuming you’ve been driving the car for a longer period of time, which is when misfires and sputtering occur.

Theoretically, diesel should not be able to get ignited within an engine running on gasoline. This is because it does not vaporize in the same way gasoline does. Gasoline engines are not designed to burn diesel. It means that, if your car runs out of gasoline, its engine will shut down, regardless of the fact that you added diesel fuel prior to that.

What to Do?

The first thing you need to do, having recognized the mistake, is shut off the engine without attempting to restart it. By doing so, you increase the chance of the wrong fuel remaining within the tank, where it can do less damage. On the other hand, by attempting to restart the car, you increase the likelihood of the wrong fuel spreading out and entering the engine, thus risking its internal components being affected, which adds to the damage. Have in mind that certain car models begin mixing fuel before you actually start the engine, so make sure you don’t put your key in the ignition.

Pouring Gasoline into a Diesel Car


The next step is calling for a tow truck for the purpose of going to a professional car service, where the wrong fuel will be pumped out of both, the fuel system and the tank. Following that, your tank will be taken apart and washed thoroughly. Then, if everything is in order, pour the right fuel into the car and pick up where you left off.

Concentration Is the Best Form of “Filtration”

As you could’ve figured out while reading this text, pouring the wrong fuel into your car can produce serious consequences in the form of expensive repairs and car part replacements. To make matters even worse, insurance companies don’t cover this type of situations, which means it’ll be up to you to cover all the expenses. With that in mind, we bet you’ll keep your eyes wide open the next time you go to a filling station.

We hope that you’ve found this article useful. For any questions, unknowns and suggestions you may have, please, feel free to contact us.

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