Incorrect fuel in your Audi S4? Diesel in a Petrol Audi?

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Audi Fuel Drain


Filling Diesel in a Petrol Audi is a common mistake. And its remedy depends upon a few things. If you want to find out what it is best to do to fix it then read on.
Let us discuss the main factors to think about when choosing whether to get a fuel drain:

  1. How much Diesel did you put in the Audi, taking into consideration that the fuel tank capacity of the Audi S4 is usually roughly 62 litres?
    1. A small amount of Diesel, something like 3.1 litres of Diesel in a Petrol S4 will generally not really be a major problem. Experience has proven to us that anything under 3.1 litres (which is approximately 5% of the entire fuel tank capacity) is in many instances capable of being sufficiently diluted simply by wholly topping the tank with Petrol.
      It's quite unusual to find an automobile experiencing difficulties because of under 5% incorrect fuel contamination. Bear in mind that it is very infrequently found - definitely not impossible to find. There are actually a few motor vehicles that don't endure any level of contamination in the slightest.
    2. Between 3.1 and 6.2 litres of Diesel in the Audi (from 5 to 10%) is really a 50/50 scenario. Our expertise has demonstrated that as many drivers get away with this as all those who don't. Any time you are figuring out whether to risk it and just simply fill it up consider that it is just like gambling your car on black - you will have a 50/50 chance of it working out.
    3. Anything over 6.2 litres of Diesel in a Petrol S4 must straightaway be drained out because your likelihood of getting away with that quantity of contamination is certainly below one in fifty - seriously huge odds.
  2. Put some Diesel in a Petrol Audi and drove it: Have you noted any performance problems after putting the bad fuel in your S4? If so, get it drained regardless of the volume of Diesel or even the contamination percentage. Still driving a car that is already beginning to suffer from the effect of wrong fuel contamination can likely lead to progressively more harm being caused to your fuel system components.
  3. Do you want reassurance?
    Then get it drained. Regardless of contamination ratio, there is always a certain level of risk affiliated with operating a Petrol vehicle on Petrol contaminated with the incorrect fuel. Likely implications of driving a car on the wrong fuel normally include the engine refusing to start, running lumpy, loss of power, wearing of the high-pressure pump, worn or bunged injectors, and so forth. These are some of the most frequently seen Diesel in Petrol signs and symptoms, and if you recognise any of them then stop driving and get it drained asap.

Avoid having any jack-of-all-trades to attend your car. We are Audi experts and have the certification and knowledge required to make certain you get back on the road with little hassle or worry.

Put Diesel in a Petrol Audi

Accidentally put Diesel in a Petrol Audi? Or possibly even put contaminated fuel in your Audi S4?

Give us a call for Assistance & Advice

Give us a call and obtain sincere guidance and practical assistance for your specific circumstances

We show up and do a fuel drain

We can go to you to undertake the complete fuel drain & clean right there on scene

All done & You Get Moving Once again

When we have completed you can get back moving and get on with your trip

Wrong Fuel Drain Specialists

We are the primary wrong fuel drain professionals in the UK, having nationwide service, for Audi motorists in particular. We mainly deal with:

  • Unleaded petrol in your Diesel Vehicle
  • Diesel in an Unleaded Petrol Car
  • AdBlue fuel contamination
  • Water fuel contamination

We are Audi specialists and have successfully drained thousands of Petrol Audi vehicles. Whether or not it is roadside, on a filling station forecourt, or even at home, we are able to get you on the road again.

The Process

The method of removing Diesel from a Petrol car is essentially exactly the same for the vast majority of cars. Of course it does vary a little as each make has their unique distinct fuel system. Even so it still adheres to the following points:

Petrol in Diesel Audi

Fuel Drain

Empty the Fuel Tank

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Wrong Fuel Drain Audi

System Flush

Clean out the fuel lines & pumps

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Petrol in Diesel Drain Audi

Vehicle Restart

Get the car up and running again

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Diesel in Petrol FAQs

When someone has put Diesel in a Petrol car they have a few very common questions. So we have compiled a list of the most Frequently Asked Questions for you

I put Diesel in a Petrol car and drove it. What do I do?


Turn off the car as soon as possible and call us. Continuing to run a vehicle on the wrong fuel can potentially damage it. We will be able to give you advice and assistance based on your circumstances

Will driving a Petrol car on Diesel cause damage to it?


It can. However, if the problem is caught and remedied quickly the risks will be minimal. Of the 1,500 vehicles we attend every month, less than 0.5% have suffered and substantial damage requiring parts replacement.

How much Diesel can I get away with in a Petrol car?


The safe answer is none. However you might be able to get away with a very low contamination ratio. That being said, we always highly recommend draining anything over a 5% contamination ratio asap.

I know about petrol in diesel, but what about Super Unleaded?


Putting Super Unleaded, or Shell V-Power, BP Ultimate Unleaded, etc, will have the exact same effect as putting regular unleaded petrol in your diesel car and will need to be drained out and flushed.

Will getting you to do a fuel drain void my warranty?


No! The EU Block Exemption Regulations clearly state that "the work can be carried out by as long as that garage uses manufacturer approved parts and correctly follows the manufacturer's service schedule."

Can I top it up with Petrol and add some 2-stroke oil?


This might work on some vehicles in some cases, but in the majority on instances it won't and you risk damaging the Lambda sensors as well as fuel pump and injectors, just as a regular misfuel.

Contact Us

Should you have any queries or require help please Call us!
We can get you on the road once again.

24 hour Audi Helpline

0333 366 0103

Our Corporate Office

Fuel Fixer Ltd, Linx House, 147 London Road, East Grinstead, RH19 1ET

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