If you accidentally put diesel fuel into a car designed to run on gasoline, it will cause the engine to stall and potentially lead to significant damage.
Putting the wrong type of fuel into your vehicle is a common and potentially costly mistake. Specifically, mixing diesel fuel into a gasoline engine or vice versa can have immediate and serious consequences for your car's fuel system and engine components.
Why is Putting Diesel in a Gas Car Bad?
Gasoline and diesel engines operate on fundamentally different principles and require fuels with very different properties.
- Gasoline engines use spark plugs to ignite a mixture of fuel and air in the combustion chamber. Gasoline is a volatile fuel designed to ignite easily.
- Diesel engines use compression ignition. Air is compressed to a very high pressure, which heats it up, and then diesel fuel is injected, igniting spontaneously due to the high temperature. Diesel fuel is less volatile than gasoline.
Because of these differences, putting diesel into a gasoline engine creates a serious problem.
Immediate Effects and Potential Damage
Based on reference information from August 28, 2023, just putting diesel fuel into a gasoline car is bad enough. The reference further states that attempting to drive a vehicle with diesel in a gas engine will cause it to stall as soon as diesel reaches the intake system, potentially clogging the fuel lines and damaging the engine.
Here's a breakdown of what happens:
- Engine Stalling: Gasoline engines cannot properly ignite diesel fuel with a spark plug. When the diesel reaches the engine, it won't combust correctly, leading to misfires and causing the engine to stall very quickly, often within a short distance of starting the car.
- Fuel System Clogging: Diesel is a thicker, oilier fuel than gasoline. It can clog the fuel filter, fuel lines, and the fine nozzles of the fuel injectors, which are designed for the consistency of gasoline.
- Damage to Engine Components: Running on the wrong fuel can cause internal engine damage. Fuel injectors can be damaged trying to spray the thicker fuel, and the lack of proper combustion can lead to issues like fouled spark plugs and potentially harm the catalytic converter.
- Fuel Pump Issues: The fuel pump, designed to handle gasoline, may struggle or be damaged by pumping the thicker diesel fuel.
What To Do If You Put Diesel in Your Gas Car
If you realize you've put diesel in your gasoline car, do not start the engine.
- Do Not Start the Engine: This is the most crucial step. If the fuel hasn't circulated yet, the damage may be minimal, limited to the fuel tank.
- If You Started the Engine: Turn it off immediately if it's still running, or note that it likely stalled shortly after starting.
- Call for Assistance: Contact a roadside assistance service or a tow truck. You will need to have the vehicle towed to a repair shop.
- Drain the Fuel System: A mechanic will need to drain the contaminated fuel from the tank, flush the fuel lines, and potentially clean or replace components like the fuel filter and spark plugs. In some cases, fuel injectors may also need servicing or replacement depending on how long the engine ran and the extent of the contamination.
Taking prompt action can minimize the damage and cost of repairs.
Summary of Consequences
| Action | Immediate Outcome | Potential Long-Term Issues |
|---|---|---|
| Put diesel in gas car | Fuel enters the tank | Contamination of fuel system components |
| Attempt to start/drive | Engine misfires, runs rough, or stalls quickly | Clogged fuel lines, damaged fuel filter |
| Continue attempting to drive | Increased risk of fuel injector damage, engine damage | Costly repairs, potential catalytic converter issues |
Understanding the distinct properties of gasoline and diesel is key to preventing this issue. Always double-check the pump and fuel type before refueling.
