Does Adding a Small Amount of Diesel to a Gasoline Car Have Any Impact?

[LeBlakely]

Adding a small amount of diesel to a gasoline car does have an impact. Since the fuel injector pressure of a gasoline engine is insufficient, diesel cannot be completely atomized, leading to only partial atomization. This results in increased carbon deposits in the car, with the most direct manifestation being a lack of engine power. Methods to Address Adding Diesel to a Gasoline Car by Mistake: Remember not to start the engine to prevent diesel from entering the fuel system. Then, tow the car to a 4S shop or repair shop, drain the diesel completely, and refill with gasoline. At the repair shop, besides draining the diesel, it is also necessary to clean the fuel system, replace the gasoline filter, and conduct a comprehensive inspection. Reasons Why Diesel Should Not Be Added to a Gasoline Car: Due to the low auto-ignition point of diesel, diesel engines use compression ignition. They do not require spark plugs for ignition; instead, they rely on compressing air to raise the temperature to the diesel's ignition point, after which diesel is injected and auto-ignites. Diesel engines do not have spark plugs. If diesel enters a gasoline engine, it starts to burn violently before the spark plug ignites, causing abnormal pressure in the combustion chamber, which is known as knocking. The fuel injector pressure of a gasoline engine is much lower compared to a diesel engine. When diesel is added to a gasoline engine, it cannot be completely atomized, leading to incomplete combustion. This results in the engine feeling weak, difficulty in pressing the accelerator, increased carbon deposits, and clogged fuel injectors, among other issues.

[VanChristopher]

I accidentally added a bit of diesel to my gasoline car not long ago, just about half a liter. After starting the engine, it began to shake violently with loud noises and black smoke, which scared me so much that I immediately turned it off. Later, the mechanic at the repair shop explained that diesel is denser than gasoline, leading to incomplete combustion in the cylinders, which can cause carbon buildup and clog the fuel injectors. However, since the amount was small, it wasn't a major issue—it just got diluted. He advised me to always double-check the labels when refueling to avoid such mistakes in the future, or else hefty repair bills would follow, including towing and cleaning costs that could add up to several hundred dollars. Regular maintenance, like periodic fuel system cleaning, can also help prevent such incidents. Overall, small mistakes like this won't immediately ruin the car, but it was definitely a scary experience.

[DelJayden]

Diesel and gasoline have completely different combustion modes in engines. Gasoline is ignited by spark plugs, while diesel relies on compression ignition. If diesel is accidentally added to a gasoline car, the engine may experience incomplete combustion, emit pollutants, and lose power. A small amount (e.g., less than one liter) might cause minor issues and could be tolerated, but it's best not to start the engine to avoid damaging the fuel pump or injectors. The solution is relatively simple—contact a professional shop to drain the diesel and clean the system, usually costing a few hundred yuan. Prevention is key: always double-check the fuel pump label before refueling to avoid confusion.

[ElliotAnn]

Last week, I accidentally added a small amount of diesel fuel while refueling and was really panicked! After checking online, I found that diesel has higher viscosity and is difficult to burn in a gasoline engine, which may cause vibrations or stalling. If the car suddenly malfunctions while driving, it can be extremely dangerous. Some people said a small amount wouldn’t destroy the car, but it needed to be dealt with ASAP. I immediately turned off the engine and called a tow truck. After spending 200 bucks on cleaning, it’s much better now. I’d advise newbies like me to be extra careful—always double-check before refueling and don’t rush.