What happens if you put diesel in a gas car? Diesel can clog the fuel system, damage the engine, and cause misfires. It leads to costly repairs if not addressed quickly.
Putting diesel into a gasoline vehicle is a more serious mistake than many people might believe. Diesel and gasoline are both fuels and are meant to assist in performing a vehicle’s function. However, they are used in different types of engines to ignite and combust fuel in different ways. Gasoline engines use a spark plug to ignite and combust fuel, while diesel engines use a compression process.
Diesel fuel is thicker, denser and oilier than gasoline. This is because it is designed for a diesel engine that can withstand the aforementioned qualities. But, a gasoline engine is built to accommodate a much thinner and more volatile fuel.
Having the wrong type of fuel in the vehicle can result in serious engine problems, and in some cases, it can lead to a complete engine failure.
Contents
The Key Differences Between Diesel and Gasoline
Before we look into the problems that can result from putting diesel into a gasoline vehicle, we first need to understand the fundamental differences that exist between gasoline and diesel.
1. Fuels’ Composition
There are different chemical properties that exist between diesel and gasoline. These differences can and will result in serious problems for the engine system. The difference in chemical composition is part of the fundamental differences that exist between the two fuels.
Gasoline is a highly volatile and combustible fuel that is easy to ignite with a spark. Gasoline is refined further to be used in spark-ignition type engines.
Diesel, on the other hand is heavier and has higher density overall and has more energy per unit than gasoline and is designed to be used in compression-ignition type engines that do not use spark plugs but use compression to ignite the fuel instead.
2. Engine Design
Engine design dictates how a vehicle can be optimized to use certain types of fuel. Gasoline and diesel engines operate at different compression ratios, have different fuel delivery systems, and use different methods of ignition. This means that each engine is specifically designed to operate with a certain fuel.
Gasoline engines use spark plugs to ignite a mixture of air and gasoline fuel. They operate better with lighter and more volatile fuel.
Diesel engines use higher levels of air compression to cause ignition of the air-fuel mixture. Diesel engines are built to be tougher and can operate with the more viscous and oily characteristics of diesel fuel.
3. Fuel Delivery System
The fuel delivery systems are built to cater to the various characteristics of the fuel being used in a given engine. Gasoline and diesel engines have different fuel pumps, different fuel injectors, and different fuel filtration systems that are used in the engines. This makes the engines incompatible to accept the wrong type of fuel.
Gasoline engines have fuel pumps and fuel injectors that work with the lighter viscosity of gasoline.
Diesel engines have fuel delivery systems that work with the higher viscosity of diesel fuel.
What Happens When You Put Diesel in a Gas Car?
When someone puts diesel fuel in a gasoline-powered vehicle, they can face a lot of issues. Diesel fuel is not compatible and is harmful right away.
1. Clogging of Fuel Injectors and Fuel Lines
Diesel fuel is much thicker than gasoline, and it can clog and damage the fuel lines and injectors that are made for gasoline. Diesel can coat the fuel injectors so that they can’t spray fuel properly into the combustion chamber, and the result is poor fuel distribution that can cause engine misfires and possibly cause the fuel injectors to totally fail.
2. Combustion Issues and Engine Misfire
Gas engines are designed for fuel to combust after being ignited by a spark. However, diesel engines are a different story. Diesel fuel combusts at a higher temperature, and as such has to be worked under compression. Because of this, using diesel fuel in a gasoline engine, leads to engine misfires, rough idling, and overall poor engine performance.
There are varying degrees of misfire. In the worst case scenario, the engine does not run and may not even be able to start. In less severe cases, it may run partially before stalling.
3. Damage to The Fuel Pump
Gas engines have fuel pumps designed to take in fuel that is thinner (only gasoline). Because diesel is far thicker and almost oil like, it creates strain on the fuel pumps, potentially causing them to overheat as well as sustain premature wear and tear, or even break. Fuel pumps are expensive to repair, so diesel fuel in a gasoline engine can get expensive.
4. Blocked Fuel Filter
Fuel filters perform the essential function of capturing dust and debris before fuel is funneled into the engine. If diesel is mistakenly put in a gasoline vehicle, the fuel filter could clog more easily due to the higher viscosity. If the filter gets blocked it can lower the fuel flow going into the engine causing poor engine performance. In extreme cases it can completely stop the fuel flow.
5. Mechanical Damage and Engine Overheating
Gasoline motors are created to run at a certain temperature which diesel is not capable of. If the gasoline engine is run with diesel fuel then the operating temperature of the engine will be too high which can cause the engine to overheat and potentially mechanical issues over time. These issues can include warped pistons, damaged cylinder heads and damaged seals.
6. Contaminated exhaust system
With gasoline and diesel fuel combustion, there are a lot of temperature and combustion process differences, which results in a different type of combustion. Diesel fuel makes more of higher soot concentration and particulates which can negatively affect the exhaust system. In particular, the catalytic converter and muffler can be impacted and over time can cause the exhaust system to function poorly and the engine can also lose performance.
What Should You Do If You Accidentally Put Diesel Fuel In Your Car?
If you’ve put diesel fuel in your gas car by mistake, there is no need to panic. Follow these steps to minimize damage to your car:
1. Do NOT turn on the car
Most importantly, do NOT turn on the car. If the car is turned on, the diesel fuel will get pumped into the fuel system, and the fuel injectors will get damaged. The good news is if the car has not been turned on, there is still no major damage to the engine.
2. Get your car towed to a mechanic
If the car has been turned on, get the car towed to a mechanic. You should NOT drive the car since that will cause a lot more damage to the car.
3. The mechanic will have to drain the diesel fuel
Once the car is towed to a mechanic, the first thing they will do is drain the diesel fuel. This is to ensure that there is no more diesel fuel in the car. This lessens the future risks to your car.
4. Fuel System Flush
Once the tank is drained, the mechanic will flush the fuel system. This involves cleaning the fuel lines, fuel injectors, and the fuel filter. A good flush will remove diesel fuel residue to prevent a clog and other damage.
5. Fuel Filter Replacement
The fuel filter is likely contaminated with diesel, and after draining and flushing the fuel system, a mechanic will replace the fuel filter so that it can fuel with gasoline without trouble.
6. Check for Engine Damage
The mechanic will check the engine for diesel damage. This includes examining the spark plugs, fuel injectors, and the combustion chambers. If there is any damage, the mechanic will replace any components that require it.
How to Avoid Putting Diesel in a Gas Car
Preventing this blunder is less complicated than the solution to the damage. Here are some recommendations for avoiding putting diesel in a gas vehicle.
1. Checking the Fuel Pump Twice: When you go to fill up your tank, check the fuel pump and the label twice. Diesel pumps are typically green, but you need to check that you are using the correct fuel type.
2. Teach Others About the Car: If more than one person drives your vehicle then it’s important to educate them on the difference between gasoline and diesel. Most incidents are because of lack of knowledge, so informing fellow drivers will help.
3. Fuel Filter or Locking Fuel Caps: They make locking fuel caps to fit most fuel fill openings, and some vehicles are manufactured with locking fuel fill caps. These can help with guessing games especially with drivers who are unfamiliar with the vehicle.
Frequently Asked Questions
Here are some FAQs about putting diesel in a gas engine –
- Is it okay to mix gasoline and diesel?
No. It is never okay to mix gasoline and diesel. If diesel is put in a gasoline engine, it could severely damage parts of the engine.
- What are the risks of driving a car that has diesel in the gas tank?
The car could misfire, the engine damage could include a broken fuel pump and clogged fuel injectors. It is definitely not worth the risk!
- Is it possible to fix a gas car that has diesel fuel in it?
The diesel fuel has to be removed and the gas tank cleaned before the fuel system is cleared. All of this can only be done by a qualified mechanic, whom the car must be towed to.
- Is it possible to fix this problem by myself?
The diesel fuel has to be removed AND this means that legal and qualified mechanics should be left to do this.
- What can be done to avoid putting diesel in a gas car?
You can put an educational sticker or a lockable gas cap to do the most. Also, make sure to tell others not to drive it. Checking the pump can also help.
Conclusion
Putting diesel fuel in a gasoline car creates damaging consequences. The diesel fuel and gasoline will not mix and in fact, will destroy the vehicle’s fuel system, exhaust system, and engines. Once diesel fuel is mixed with gasoline, it causes engine misfires, and fuel injectors will become clogged. In order to prevent further damage to the vehicle, the engine must be turned off and professional help is needed. If people educate one another and pay attention when refueling, most mistakes can be avoided.
