1. Assess the Situation:
* How much gasoline? A few gallons are less damaging than a full tank.
* Did you already start the engine? If so, the damage is likely greater. The gasoline will have gotten into the fuel injectors, engine oil, and potentially the catalytic converter.
* What type of fuel system? Modern diesel systems are often more sensitive than older ones.
2. Immediate Actions (Crucial):
* Do NOT start the engine. This is the most important step. Running the engine with gasoline in the fuel system can cause catastrophic damage.
* Drain the fuel tank. This is the most important step to fixing it. The best way to do this is to have the tank professionally drained, often using a pump. You can try to siphon it, but it's messy and less efficient. Be extremely careful as gasoline is flammable.
* Find a professional mechanic as soon as possible. Don't attempt extensive repairs yourself unless you have significant diesel engine experience.
3. Professional Repair (Likely Necessary):
Depending on how much gasoline was added and whether the engine was started, the mechanic will likely perform some or all of these steps:
* Complete fuel tank draining: Ensure all gasoline is removed.
* Flush the fuel lines and filter: Gasoline can damage seals and filters. The entire fuel system needs a thorough flush with clean diesel fuel. This often requires removing and cleaning or replacing the fuel filter(s).
* Check the fuel injectors: Gasoline can damage the delicate seals in the injectors. They may need cleaning, testing, or replacement.
* Check the fuel pump: The pump may need cleaning or replacement.
* Oil change: Gasoline in the fuel can dilute the engine oil, reducing its lubricating properties. An immediate oil change is crucial.
* Inspect the catalytic converter (if applicable): Gasoline can damage or destroy this component.
* Check for damage to other components: Gasoline may have damaged sensors or other parts of the fuel system.
4. Prevention:
* Clearly labeled fuel nozzles: Diesel fuel nozzles are usually a different color and shape than gasoline nozzles. Pay close attention.
* Double-check before fueling: Take your time, confirm the nozzle fits correctly, and check the fuel gauge and vehicle paperwork before beginning to fuel your vehicle.
In short: The best approach is to call a roadside assistance service or tow truck immediately. Do not attempt to start the vehicle, and then get it to a qualified diesel mechanic as quickly as possible for proper diagnosis and repair. The cost of the repair will vary significantly depending on the extent of the damage. It could range from a few hundred dollars for a minor contamination and flush to several thousand dollars if significant engine components need replacement.
