What Happens If You Put Gasoline In A Diesel Engine? (And What to Do)

You will see various colored handles at gas stations that identify the fuel types. While it’s difficult to miss the appropriate one for your vehicle, there are times when you could be distracted, inadvertently putting gasoline into your diesel engine. Now what? 

This article will explain what happens to your diesel car if gasoline is used instead. The fuel differences will be discussed and we'll tell you how to reduce damage. 

Differential Features Between Diesel And Gasoline

Although both gasoline and diesel fuel are made from crude oil, there are many differences between them. Diesel fuel will have thicker consistency that gasoline. The fuel also weighs one pound heavier than regular gasoline. 

Gasoline evaporates, while diesel doesn’t. Plus, gasoline doesn’t contain lubricating properties, but diesel fuel does. Diesel engines are self-igniting and do not use spark plugs. 

A diesel engine has a lower compression ratio than a gas engine. The differences in compression ratios mean that fuels react very differently to different engines. 

What happens if you put gasoline in a diesel engine?

Gas can damage the diesel engine's fuel pump and injectors if it is injected into a petrol engine. Gas does not possess the same lubrication qualities as diesel. Uncontrolled explosions can cause damage to internal parts of the engine.

If you use gasoline to fill up your diesel tank, there are some things that can damage your engine. This is a detailed listing of possible problems when you put gasoline into your diesel engine.

1. No ignition

The diesel engine simply wasn’t manufactured to ignite fuel. Unlike diesel fuel, gas wasn’t made to ignite automatically, which is why a spark plug is needed.

There are no sparkplugs that can be used to ignite a diesel engine when gas is added. The engine would not start if there wasn't enough diesel fuel in the gasoline. 

2. No Lubrication

Diesel fuel, which also acts as a lubricant for the engine's internal components is very similar in appearance to oil. Because gasoline acts instead as a solvent, it does not offer any of the lubricant.

Gas can contaminate your engine and cause other problems. The engine will run if it is not lubricated. Metal parts can rub together and get damaged. 

3. Fuel System Damage

It isn’t just the engine you need to worry about, but also the diesel system. It is equipped with specially designed fuel filters, pumps, and injectors to deal with diesel. 

The door to potential damage opens when gas is added to the fuel system. To repair damage, it may be necessary to completely replace the fuel system. 

4. Uncontrollable Detonation

Many parts move inside the diesel engine just as you'd find them in a gas engine. There will be pistons, rods, and other components that move. 

Due to the differences in gasoline's weight and other properties, the diesel engine can explode uncontrollably, causing a chain reaction of shock waves. The components simply won’t be able to handle this level of detonation, leading to irreversible damage. 

5. Black Smoke

Diesel fuel's flash point is 126°F. Gasoline has a flash point of 70 degrees Fahrenheit. 

Gas isn’t going to ignite in a diesel engine as well, leaving behind lots of unburned fuel. The exhaust might then emit black smoke. This is not only dangerous for the system but also could cause clogging of various sensors. 

6. Severe Engine Damage

These conditions could lead to engine damage. It is possible to reduce damage by being caught in time.

You could endanger the engine if the system is not checked regularly. You will likely need to replace your engine if you drive for too long. This can be quite costly. 

Here's what to do if you put gasoline in a diesel engine

Once you are aware that your fuel is incorrect, it's time to correct the problem. Obviously, you don’t want to panic, which is easier said than done.

These steps will guide you when you are putting gas into your diesel engine.

1. Avoid starting the engine. You must keep the vehicle where it is until you call a towtruck.
2. Do not turn on the ignition. It is not the right time to switch on the radio. You can activate the pump and fuel injectors by flipping the key to ON.
3. You can pull over if you're already driving. Park the car until you can get a tow truck. 
4. Take your truck to a reliable service center. You can do the job yourself if you're not able to.
5. Flush the fuel tank. You can clean out the entire fuel tank and turn off the ignition if the system is not in use. 

It will also save you a lot headaches by not putting fuel into the diesel engine. Make sure you are using the correct nozzle when entering the fuel station.