An age-old debate that has stood the test of time, gasoline or diesel? Both are readily available at your local gas station, but are they used interchangeably? What are the advantages of one over the other? Would using the lime green pump really hurt my sedan?

Whether you are shopping for a vehicle, looking for a job in the automotive industry, or simply navigating a gas station, it is best to know the differences between the two fuels. This guide will go over common questions surrounding diesel and gasoline.

Background

Diesel and gasoline start as crude oil after being mined from underground reservoirs. It is through the refinement process that the two are separated into different types of fuel; gasoline being more refined. Both have very similar functions that allow the car to move. The engines use internal combustion and a string of quick explosions that turn the fuel into the required mechanical energy needed to move the vehicle. The contrast is how this process comes about. 

In gasoline, the fuel is mixed with air that has been compressed by the engine pistons. The air is then ignited with the help of internal spark plugs. For diesel engines, the air is first compressed to increase the temperature required for spontaneous ignition. The fuel will then ignite once it hits the air and you’re off! If this type of combustion were to happen in a gasoline engine, there would be serious damage done to the vehicle.

Diesel Engines

Generally, diesel is the more costly option of the two fuels which is predominantly due to higher state and federal taxes. This fuel is also heavier and more volatile than gasoline. This extra weight allows it to evaporate more slowly inside the engine, which in turn benefits the overall fuel efficiency of the vehicle. One of the more important differences between the two fuels is that diesel engines tend to have better fuel economy because they are more thermally efficient. Meaning a diesel engine will need less fuel to achieve the same amount of work as a gasoline engine.

Diesel is the more durable engine type, due to the design of the engines and the use of diesel fuel. These engines are typically found in different types of equipment and vehicles that can range from semi-trucks, trains, agricultural machinery, etc. Diesel can also be used to power certain types of generators, which tend to last longer and are more fuel-efficient. Diesel engines are favored more for big machinery because they can produce more energy at lower rates per minute (RPM) and provide more torque. These engines tend to be much more expensive to produce than gasoline engines because of their extra equipment and heavy-duty internal components.

Gasoline Engines

Gasoline engines are compiled of hundreds of little parts that are extremely precise in their placement. Since it is typically the common driver that uses gas engines, these intricate parts have stress put on them due to the routine stop-and-go driving style. The maintenance and acquisition costs for these engines are significantly lower than they are for diesel.

As previously stated, diesel engines have a higher compression ratio due to their thermal efficiency, allowing explosions to occur and produce more energy. A gasoline engine can never achieve the same compression ratio, as the fuel would be ignited by the excess heat resulting in unwarranted explosions inside the engine. 

What Would Happen If I Used the Wrong Pump?

Let’s just make it simple, DO NOT. Gasoline engines are not made to combust diesel fuel and will make the vehicle stop running. Since diesel fuel is thicker than gasoline, it would be difficult for the fuel to move through the fuel pump. Diesel cannot pass through the vehicle’s filters, and the fuel that ends up making it to the engine will clog the fuel injectors. 

On the other hand, if you mistakenly put gasoline into your diesel engine, avoid turning on your vehicle altogether to avoid serious engine damage. Both situations would require you to remove the fuel tank in order for it to be emptied and cleaned. If either case were to arise, it’s best to not drive the vehicle and call a trusted professional to assist you. 

Your friendly reminder to always be aware when pumping gas!

Both engines have their own advantages that may be more suitable for your driving habits. We service both diesel and gasoline vehicles at all of our locations! No matter which engines your vehicle has, our fast and friendly technicians will be able to assist you and answer any questions you may have.