Cars
3 steps
Filling a car with the wrong fuel is a common situation, but it can cause serious damage to the engine and fuel system. This article explains how to act immediately, the risks involved, and how to avoid future problems. Learn to identify warning signs and the correct measures to protect your vehicle.
What happens when the wrong fuel is added?
Each engine is designed to operate with specific fuels. When the wrong fuel is added, combustion may be impaired, affecting components such as injection pumps, fuel injectors, and lubrication systems. The effects vary according to the type of fuel used, the amount added, and whether the engine has already been started.
I noticed the mistake before starting the car
This is the most favorable situation. If the engine has not been started, the wrong fuel remains concentrated in the tank and does not circulate through the fuel system. In this case, the safest recommendation is to stop refueling immediately, do not start the engine or move the vehicle, and request technical assistance for evaluation.
I noticed the mistake after the car was already running
If the engine was started, the wrong fuel begins to circulate through the system, increasing the risk of damage. If you notice problems such as loss of power, excessive smoke, or dashboard warning lights, stop using the vehicle and seek specialized assistance.
Steps to resolve the situation
Essential actions to minimize vehicle damage
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1
Stop refueling
Stop the refueling process immediately to avoid making the mistake worse.
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2
Do not start the engine
Prevent the wrong fuel from circulating through the fuel system.
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3
Request technical assistance
Seek professional evaluation to drain the tank and check for damage.
Risks of incorrect fuel by vehicle type
| Incorrect Fuel | Risk for Flex-Fuel Engines | Risk for Single-Fuel Engines | Recommended Action |
|---|---|---|---|
| Gasoline in diesel engines | Changes in performance and increased emissions | Damage to the injection pump and common rail system | Avoid starting the engine and seek assistance |
| Diesel in gasoline engines | Possible changes in performance | Combustion failures and loss of power | Stop using the vehicle and seek technical evaluation |
Important Tips
Always check the fuel type recommended in the owner's manual.
Clearly tell the attendant which type of fuel you want.
Avoid refueling when in a hurry to reduce the risk of confusion.
Frequently asked questions
Quick answers to common questions.
What happens if I start the engine with the wrong fuel?
The wrong fuel can cause serious engine damage, such as failures in the injection pump, common rail system, or fuel injectors. Improper combustion can also cause faults detected by the vehicle's electronic system.
How can I avoid this problem in the future?
Confirm the recommended fuel in the owner's manual, clearly tell the attendant which fuel you want, and avoid refueling when in a hurry. Use identification labels and check the pump before refueling.
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