What to Do If You Fill Your Car with the Wrong Fuel?
3 Answers
Solutions for filling your car with the wrong fuel are as follows: 1. Adding low-quality fuel is more severe than adding fuel with the wrong octane rating. Using substandard gasoline can degrade engine performance and damage components like pistons and fuel pumps. However, signs of using poor-quality fuel are often noticeable, such as valve noise or reduced power, which may indicate low octane fuel. If the engine struggles to start, suspect fuel contamination—excessive impurities, adulteration, or diluted gasoline. In such cases, do not force-start the engine; instead, contact a specialized auto repair shop or 4S store immediately. 2. Adding lower-octane fuel instead of higher-octane fuel: If the difference is minor (e.g., 97 to 93 or 93 to 90), the vehicle may exhibit reduced power and increased fuel consumption. No major engine damage occurs if this isn't prolonged. However, for significant differences (e.g., 97 to 90), drain the fuel tank before starting the engine and arrange for a professional cleaning of the tank and fuel system. 3. Adding gasoline to a diesel engine: The engine may start initially but quickly lose power. After driving, unusual noises, unstable idling, and white exhaust smoke may appear. If detected early, replacing the fuel without further engine adjustments may suffice. 4. Adding diesel to a gasoline engine: This is more serious. Since gasoline and diesel combust differently, symptoms like engine shaking, black smoke, or failure to start may occur. Continued use can damage the entire fuel system or even destroy the engine. If this happens, immediately contact a repair shop to clean the tank and fuel system, followed by a full engine inspection. Avoid ignition to prevent further damage. Note: Such damage is typically not covered by insurance.
If you accidentally put the wrong fuel in your car, such as adding gasoline to a diesel vehicle or diesel to a gasoline vehicle, do not start the engine immediately to prevent the fuel from being pumped into the engine and causing severe damage. I remember once seeing someone do this at a gas station—they were so shocked they immediately turned off the engine and called for help. The best course of action is to stop the car where it is, call for professional towing to a repair shop, where they can drain the tank and clean the fuel system. Don’t attempt to handle it yourself, as it could make things worse. When refueling daily, I’ve made it a habit to double-check the labels, especially when renting or borrowing a car, to save on hefty repair costs and avoid unnecessary trouble.
I've also heard about this unfortunate incident of misfueling from a friend. He rented a car out of town and accidentally filled a diesel car with gasoline, causing the car to break down not far after. It cost him over a thousand dollars at the repair shop. My advice is: if you realize you've misfueled, immediately turn off the engine and don't start it. Park in a safe spot and call your insurance company or roadside assistance. If the fuel hasn't entered the engine, you can just find a shop to drain the tank. When refueling, I always remind myself to take it slow and double-check the pump's color and label—for example, green is often for diesel, blue for gasoline. Making this a habit can help avoid such frustrating mishaps.
