What to Do If You Put the Wrong Fuel in Your Car

Putting the wrong fuel in your car is a mistake that can happen to anyone. Whether you accidentally filled a petrol car with diesel or vice versa, the consequences can be costly and stressful. Knowing what to do immediately after realizing the error can save you from expensive repairs and long downtime. This guide explains the steps to take if you put the wrong fuel in your car and how specialists like Misfuelled Car Fix can help.

Car fuel filler neck with petrol nozzle, showing the point of misfueling

How Wrong Fuel Affects Your Car

Using the wrong fuel type disrupts the engine’s operation. Petrol engines and diesel engines work differently, so putting diesel in a petrol car or petrol in a diesel car causes problems such as:

• Engine misfire or failure to start

• Damage to fuel injectors and fuel pump

• Clogged fuel filters

• Potential damage to catalytic converters or other emission components

  
  

For example, diesel is thicker and less volatile than petrol. If diesel enters a petrol engine, it can clog injectors and cause the engine to stall. Conversely, petrol in a diesel engine can cause knocking and damage the fuel system.

Immediate Steps to Take After Misfuelling

If you realize you have put the wrong fuel in your car, act quickly to limit damage. Follow these steps:

1. Do not start the engine

   Starting the engine circulates the wrong fuel through the system, increasing damage. If you haven’t started the car, you have a better chance of avoiding costly repairs.

   
   

2. Turn off the ignition and remove the key

   This prevents accidental starting and helps avoid further contamination.

   
   

3. Call a specialist like Misfuelled Car Fix on 0800 999 1182

   Experts can advise you on the best course of action and arrange for your car to be safely drained and cleaned.

   
   

4. Do not attempt to drive the car

   Driving can push the wrong fuel deeper into the engine and fuel system, making repairs more difficult and expensive.

   
   

How Specialists Fix a Misfuelled Car

Specialist companies like Misfuelled Car Fix have the tools and knowledge to handle misfuelling safely and efficiently. Their process typically includes:

• Draining the contaminated fuel tank

They remove all the wrong fuel from the tank to prevent further damage.

• Flushing the fuel system

This step clears the fuel lines, injectors, and filters of any remaining incorrect fuel.

• Checking the engine and fuel pump for damage

Specialists inspect critical components to ensure no lasting harm.

• Refilling with the correct fuel and testing the vehicle

After cleaning, the car is refueled properly and tested to confirm it runs smoothly.

Using a professional service reduces the risk of long-term damage and gets your car back on the road faster.

Common Misfuelling Scenarios and How to Avoid Them

Misfuelling can happen in various ways. Understanding common scenarios helps prevent mistakes:

• Filling a petrol car with diesel

Diesel pumps often have larger nozzles, but some petrol cars have wide filler necks that allow diesel nozzles to fit. Always check the pump label carefully.

• Filling a diesel car with petrol

Petrol nozzles are usually smaller, so they may not fit into diesel cars. However, some older diesel cars have filler necks that allow petrol nozzles, increasing risk.

• Using the wrong grade of fuel

While less damaging than misfuelling, using a lower grade petrol than recommended can affect performance.

• Renting or borrowing unfamiliar vehicles

Drivers unfamiliar with a car’s fuel type are more likely to make mistakes. Always double-check before filling.

To avoid these errors:

• Always read the fuel pump label before filling.

• Look for stickers or labels on the car near the fuel cap indicating the correct fuel type.

• If unsure, ask station staff for help.

• Avoid distractions while refueling.

  
  

What to Expect in Terms of Cost and Repair Time

The cost of fixing a misfuelled car depends on several factors:

• How much wrong fuel was added

• Whether the engine was started or driven

• The type of vehicle and engine

• Damage to fuel system components

  
  

If you catch the mistake before starting the engine, the repair may only involve draining and flushing the fuel system, costing a few hundred pounds. If the engine ran on the wrong fuel, repairs can escalate to thousands due to injector or pump replacement.

Repair time varies from a few hours for simple draining to several days if parts need replacement.

When to Contact Misfuelled Car Fix

If you suspect you have put the wrong fuel in your car, contact a specialist immediately. Misfuelled Car Fix offers expert advice and fast response to minimize damage. Their helpline 0800 999 1182 is available to guide you through the process and arrange professional assistance.

Waiting or trying to fix the problem yourself can lead to more damage and higher costs.

Preventing Misfuelling in the Future

Prevention is the best way to avoid the stress and expense of misfuelling. Here are some tips:

• Always double-check the fuel type before filling.

• Use fuel caps with clear labels.

• Keep a note of your vehicle’s fuel type in your wallet or phone.

• Avoid filling up in unfamiliar or poorly marked stations.

• Consider installing a misfuel prevention device if available for your car model.

  
  

Being cautious and aware can save you time and money.