What Happens When Your Car’s Tank Is Filled With Wrong Type of Fuel – Explained!

But every error has repercussions. If a mistake is minor enough, such as choosing the incorrect route to your destination, it may only result in a small increase in fuel consumption. Let’s have a look broadly at wrongly filling up fuel inside a car and what could be the consequence of such a mistake.

Commonly, most vehicles run on only two types of fuel: either petrol or diesel. Therefore, it is possible that anyone can goof up when these types of fuel are available under the same premise. However, two possibilities might be likely when there is an instance of wrongly filling up a car’s tank.

1. Filling diesel into a petrol car

Though the diesel dispenser usually has a larger nozzle as compared to the petrol dispenser, these large nozzles do not fit into the smaller necked gasoline tanks. However, it is possible to make a mistake and fill the vehicle with the wrong type of fuel. It happens when someone does not have enough knowledge about filling up fuel.

Under normal circumstances, the diesel nozzle does not insert easily into the narrow neck of a gasoline tank.

What happens when you fill diesel into a petrol car?

Petrol is more of a refined fuel and it requires spark plugs for ignition inside the combustion chamber. Though, filling the diesel in a petrol car does not produce catastrophic damage. If it is done mistakenly, diesel usually coats the spark plugs and contaminates the entire fuel system. This is visible properly if a car starts to misfire just after filling up the fuel. In most cases, your vehicle might produce excessive smoke.

This is due to the lack of capacity of petrol cars to process diesel. In case, you can not realize the mistake during the filling process, it is possible to run a car over a mixture of diesel and petrol. But it is necessary that the tank contain less than five percent diesel and the rest be petrol. While diesel can easily get mixed with petrol, cleaning the entire tank and fuel lines is a better alternative if you are more concerned about your vehicle.

What should you do in the case of wrong fuel filling up (diesel in a petrol car)?

Even though this doesn't sound too bad in comparison to the harm that petrol can do to a diesel engine, the tank will still need to be drained and cleaned right away to avoid clogging the system and its parts.

Amidst such a situation, ask for help with car recovery from Service My Car. There would be no point in running a car on an entirely different fuel, even if it has been running.  It would be better to opt for fuel system cleaning by an expert.

2. Filling petrol into a diesel car

Contrary to the diesel dispenser, the petrol dispenser comes with a narrow nozzle and can easily fit into the diesel tanks. Therefore, it has a higher percentage of happening.

As people can make this mistake more easily, the consequences will be more serious. While diesel also works as lubrication along with being a fuel, petrol does not possess such a property. Once there is a mistake of filling petrol in a diesel engine, the engine turns over. There would be friction inside the engine, which puts a number of things at stake. Usually, the fuel injectors receive the initial damage, and the engine might be at risk of failure too. If this happens, nothing can save a vehicle, not even a car engine repair.

What should you do in case you fill up with the wrong fuel (petrol in a diesel car)?

There are two scenarios to take into consideration.

1. Is the engine turned over? If Not.

In case you are fortunate enough and the petrol has been filled in your diesel car. Do not try to crank the engine. If the fuel stays in the tank and does not reach the engine, there would be no issue at all.

You have to just make a call to a car recovery service like Service My Car. They definitely help you in towing your vehicle to the nearest workshop and flush your car tank as well as fuel lines. Once done, you can fill the tank up again with diesel before starting your vehicle again.

2. Is the engine turned over? If Yes.

Usually, you will know if there was any goof up in filling up the fuel.  Your car will produce a loud knocking sound instantly, and there might be an instance of smoke too. As gasoline has been circulated to each part of the diesel engine, it would definitely wreak havoc inside. If you realize the mistake, do not waste a second in stopping your car’s engine.

In this case, you are supposed to ask for roadside assistance from Service My Car. Just get your car's tank and fuel lines cleaned properly with the help of an expert. However, there might be some sort of damage under the hood.  Sometimes, it requires an engine overhaul or a complete replacement.

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