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Are Diesel Nozzles Bigger Than Gas?

It's no secret that diesel and gas fuel is entirely different. However, are the nozzles at the fuel pump different? Is one bigger than the other? In this article, we have done extensive research to answer that question for you.

Diesel nozzles are bigger than gas fuel pump nozzles. Therefore, if you attempt to put a diesel nozzle in a gas fuel tank, it will not fit. Also, it would be best if you never attempted to do this, as adding diesel to a gas vehicle can harm the vehicle.

It's not that you would try to put diesel in your gas tank on purpose. However, if you are unsure if the pump is diesel or gas, then there are ways you can tell. This article will take a closer look at putting diesel in a gas fuel tank and vice versa. In addition, we will determine the consequences of mixing these types of fuels, so read on!

A man holding a black fuel pump while opening the fuel cover of his car, Are Diesel Nozzles Bigger Than Gas?

Are Diesel Nozzles Bigger Than Gas?

If you didn't know already, diesel nozzle size, or mouth, is bigger than the mouth of gas pumps. This means that it is physically impossible to put a diesel nozzle in a gas tank without modifying it or ripping out part of the fuel system. However, if you are unsure if the fuel pump is diesel or gas, there is an easy way to tell.

If you have a gas vehicle and use a diesel fuel nozzle, the fuel nozzle won't fit. Do not try to force the fuel nozzle into the tank. In addition, if you are still confused, then ask a gas station attendant. In places like Oregon, it is illegal to fuel your vehicle, so you should never have this issue in those circumstances.

Another way to know is by reading the label on the fuel pump. Nowadays, most diesel pumps are labeled "Diesel Only." However, many gas pumps will say "Unleaded" or "Regular Unleaded." On the other hand, if you don't see one of these labels, it is safe to assume that it isn't diesel fuel.

Diesel is Heavier than Gas

Diesel is heavier than gas, which has a higher octane rating. This means that if you put diesel in your car, it will stop running very quickly. When this happens, you'll need to tow your vehicle or replace the entire fuel system.

Diesel has Higher Ignition Temperature

The primary issue is that gasoline has a lower ignition temperature than diesel fuel. What this means is that the gas will ignite at a lower temperature than diesel. This can cause your vehicle to stall and possibly lead to other problems down the road if it isn't addressed immediately.

Diesel & Gas are not Interchangeable 

Putting the wrong type of fuel in your vehicle can cause severe problems. For example, many diesel engines require that you use special high-quality diesel fuel with low sulfur content. If you attempt to put this into a gas tank, then you are bound to cause damage. It won't be immediate, but it is inevitable if constantly done.

Another issue is corrosion, especially with high sulfur content fuels. The sulfur in gas can quickly corrode metal components such as fuel injectors and more. So again, it is imperative to note that even a tiny amount of fuel contamination can cause an issue.

A man holding a black fuel pump to gas up his car

Will a little bit of diesel hurt a gas engine?

Even a little bit can cause issues. For example, let's say you accidentally spilled a few drops in your gas tank and then filled up the rest with regular unleaded fuel. Unfortunately, a small amount of diesel can ruin an entire tank of gas.

This is because diesel is a thicker and denser fuel, and the gas vehicle will have a hard time flowing the fuel through the fuel pump, according to JD Power. This will then cause the fuel to clog the fuel filter and fuel injectors.

The reason is that diesel has higher cetane content than gasoline does. As mentioned before, this can cause the gas engine to run rough or stall. It can also lead to lousy mileage, reduced acceleration, and other issues. If you are unsure if there is diesel in your tank, here are some symptoms of too much diesel fuel in your car:

  • Delayed ignition/spark when starting a vehicle after refueling.
  • The engine won't crank.
  • Rough idle, lack of power, and engine brake due to fuel contamination in the engine.

If this sounds familiar, then you should have your fuel tank cleaned out immediately. In addition, you will need to look at replacing your fuel filter and injection system components.

A man gassing up his car'

What should I do if I accidentally put diesel in my car?

The best thing to do in this situation is to call a tow truck. Driving the vehicle with diesel in the gas tank will cause damage to the car. Have the vehicle taken to a mechanic's shop to have the issue addressed.

You need to act fast if you have just put diesel in a gasoline engine. If you continue to run the engine with diesel in it, you will cause significant damage. It would be best if you considered having your fuel tank drained and cleaned immediately.

The best way to avoid this is by being careful when filling up at the pump. Unfortunately, many people take their eyes off of the nozzle when pumping gas. This does not pose a problem if you put gasoline in, but it will if you put diesel fuel instead.

Will 1 gallon of gas hurt a diesel engine?

Some gas can hurt a diesel engine if you put in too much. According to Bell Performance, as little as 1% of gasoline can cause damage to your diesel engine. You have to understand that putting the wrong type of fuel into your vehicle won't cause immediate problems. This is because it isn't until you start and run the engine do you begin to see the effects of fuel contamination.

For example, it is possible that your vehicle will continue to run until you notice something isn't right. If you use an oil additive, this can be an issue that causes the engine to stall and quit running altogether.

You also have to consider that not all diesel engines are created equal. Some have high-pressure common rail fuel injectors, while others use a basic pump system.

Does insurance cover put gas in a diesel engine?

Typically your auto insurance company will not accept filing a claim for this type of situation, according to 4 Auto Insurance Quote. The owner's responsibility is to make sure they use the correct fuel when filling up at the pump.

You can contact your insurance company to see if they will accept it, but it will be a losing battle more than likely. The best thing you can do is pay attention when you are fueling up your vehicle. You will be more likely to put gas in a diesel vehicle because the nozzle will fit. In this case, double-check that you are putting diesel in your diesel vehicle.

A man holding his phone showing a car insurance app

What is the difference between gas fuel and diesel fuel?

There are a lot of differences between gasoline and diesel fuel. The most significant difference is the type of engine each one will work in. Gasoline works best in a standard passenger vehicle that requires spark ignition. On the other hand, diesel-only works in a compression ignition system.

The second issue is that you can't put gas in a diesel vehicle. The gas is the wrong type of fuel, so it causes significant damage to the vehicle when you do this.

Another difference between gasoline and diesel fuel is that gasoline comes with 10% ethanol added. When you add the wrong type of fuel to a diesel engine, you can cause more damage. This is because it causes more wear on parts and damages the catalyst in your exhaust system. The catalyst plays a significant role in converting harmful gasses into less harmful substances for the environment.

Different colored fuel pumps indicating different types of fuel

In Closing

Overall, if you make a mistake and add the wrong fuel to your vehicle, then contact a tow truck. It will cost you a tow bill but could save you from a bigger bill from repairs. Driving with gas in a diesel vehicle or vice versa can cause damages to the vehicle parts. Always double check you are putting the right fuel in your vehicle before pumping fuel.

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We would love to hear from you! So leave us a comment below!


Thursday 16th of March 2023

FALSE, i mean come on. Diesel has both size nozzles in the USA, PERIOD. thats how people put diesel in a gas car. funny how you make an entire long post of false information. i will gladly send you pictures