Gas Vs. Diesel Car Engine: What is the Major Difference?

Every car has an engine, but not every car has the same engine. The two most popular kinds of engines are gasoline-powered and diesel-powered engines. These engines are used in various types of cars and serve efficiently. 

But what’s the difference, are the two interchangeable, and what are the benefits of each?

Difference Between Gas and Diesel Engines

Both gas and diesel engines are known as four-stroke engines. The fuel and air are injected into a chamber. That air and fuel are compressed by the piston pushing up and igniting. The explosion of that fuel pushes the piston back down, and then when the piston goes back up, all the exhaust is pushed out. The cycle repeats until you run out of gas, which is hopefully never.

But that third step, when the fuel is ignited, is when things start becoming different. A gas engine uses something called a spark plug. If you have a four-cylinder engine, you have four spark plugs.

Diesel engines don’t have spark plugs. Instead, the air and fuel are much more compressed. And that rapid compression generates heat, which lights the gasoline rather than an external spark. But if gasoline engines and diesel engines use the same four-stroke process, why can’t they use the same fuels?

Difference Between Gas and Diesel

There are two main differences between gas and diesel: thickness and combustibility. The former is fairly easy to understand. Gasoline is much thinner than diesel, whereas diesel is similar to oil in consistency. But despite the richer mixture, it’s actually less combustible than gasoline. Not that it wouldn’t catch fire if you held a match to the fuel, but gasoline would light much faster.

Don’t ever use diesel fuel in a gas engine or gas in a diesel engine. Unless you want to destroy the engine, in which case go ahead. Putting diesel in a gasoline car would clog up the fuel pumps and injectors, which weren’t designed to handle the heavy mixture.

Diesel engines are durable and capable of running on different fuels such as biodiesel, Dimethyl Ether, and even used vegetable oil. In fact, diesel engines were originally designed to run on groundnut oil (according to experts), a cheap and accessible resource to help stimulate an automotive boom worldwide. However, they can’t run on gasoline.

This is partly because all the aforementioned fuels, and diesel itself, are closer to oil. They have lubricating qualities that keep the engine operating silky smooth as the diesel flows through it. In other words, if diesel fuel didn’t have that lubricating quality, it’d gunk up the engine. Gas is just gas, it wasn’t meant to lubricate anything, which would damage the parts and total the engine.

So don’t mix up the two, it’s dangerous to your car. But when you put the right kind of fuel in the right engine, diesel to diesel and gas to gas, they have some distinct advantages.

Which is Better: Gas or Diesel?

Deciding which is better all depends on what you’re looking for in a car. Both engine choices are great at their respective jobs, but you wouldn’t want to bring a diesel to a gas fight.

The advantage of a gas engine is that it can be smaller while still operating at a higher RPM, whereas diesel engines are big and can only go so fast. Gas engines are also cheaper to maintain. And if you’re into saving the environment, but can’t afford electric cars, then gas is also the cleaner option.

Diesel engines, on the other hand, run forever. They might be loud, unlike gas engines, but they’re the go-to option for long-distance drives. If you give them the fuel, they’ll just keep going. They also tend to be more torquey, and capable of pulling heavier loads. This explains why they operate quite happily and powerfully at low RPMs.

Conclusion

If you’re looking for high speed and performance, you’ll want a gas-burning engine. But if you need to tow, or go on long road trips, then a diesel is the better option.