Contaminated fuel in a Mini Cooper S? Diesel in your Petrol Mini?

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Mini Fuel Drain


Filling up with Diesel in a Petrol Mini is a well-known mistake. And its solution depends upon several things. If perhaps you want to know what you need to do about it then please read on.
Here are the most crucial factors to take into account whenever making a decision whether to get a fuel drain:

  1. What level of Diesel did you put in the Mini, keeping in mind that the fuel tank capacity of the Mini Cooper S is normally about 50 litres?
    1. A tiny quantity of Diesel, as little as 2.5 litres of Diesel in a Petrol Cooper S will in most cases not really be a massive problem. Experience has demonstrated to us that an amount under 2.5 litres (approximately 5% of the overall fuel tank capacity) is oftentimes able to be sufficiently diluted by thoroughly filling the remainder of the tank with Petrol.
      It's very uncommon to encounter a car or truck having problems due to less than 5% incorrect fuel contamination. Do not forget that it's infrequently found - certainly not impossible to find. There are actually some automobiles that won't endure any degree of fuel contamination whatsoever.
    2. In between 2.5 and 5 litres of Diesel in the Mini (from 5 to 10%) is more of a 50/50 situation. Our expertise demonstrates that as many drivers get away with it as all those who break down. When you are deciding upon whether to risk it and just fill it up consider that it is much like gambling it all on black - you will have a 50/50 chance of it being ok.
    3. Anything in excess of 5 litres of Diesel in a Petrol Cooper S must immediately be drained as your probability of getting away with that quantity of contamination is very likely less than one in 50 - truly huge odds.
  2. Put Diesel in a Petrol Mini and drove it: Have you noticed any performance problems as a result of putting the wrong fuel in your Cooper S? In that case, have it removed irrespective of the quantity of Diesel or the contamination percentage. Proceeding to run running a vehicle that is already starting to suffer the effect of wrong fuel contamination can definitely be responsible for progressively more harm being caused to your fuel system components.
  3. Do you want reassurance?
    Simply get it removed. Whatever the contamination ratio, there is inevitably some degree of threat in connection with operating a Petrol engine on fuel contaminated with the incorrect fuel. Likely outcomes of driving on the wrong fuel include the engine not starting, running lumpy, loss in power, wearing of the high-pressure pump, damaged or clogged injectors, and so forth. These are a few of the commonest Diesel in Petrol signs and symptoms, and if you recognise any of them cease driving and get it drained right now.

Steer clear of getting any unqualified so-and-so to attend your vehicle. We are Mini experts and have the accreditation and experience needed to make certain that you are back on the road with little hassle or trouble.

Put Diesel in a Petrol Mini

Accidentally put Diesel in a Petrol Mini? Or possibly even put contaminated fuel in your Mini Cooper S?

Call us for Assistance & Recommendations

Contact us and obtain honest advice and practical assistance for your precise circumstances

We show up and do a fuel drain

We can go to you to perform the full contaminated fuel retrieval & purge there on scene

All done & You Get Going Once again

Once we have finished you should be able to get back on your way and get on with your trip

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain specialists in the UK, having countrywide cover, for Mini motorists particularly. We principally fix:

  • Unleaded petrol in Diesel Auto
  • Diesel in Unleaded Petrol Auto
  • AdBlue fuel contamination
  • Water contamination

We are Mini specialists and have successfully drained thousands of Petrol Mini vehicles. Even if it is roadside, on a station forecourt, or even at your home, we are able to get you going again.

The Process

The method of draining Diesel from a Petrol car is basically similar for most vehicles. Obviously it may differ to some degree as every manufacturer has their unique fuel system. Even so it still basically observes the below principles:

Petrol in Diesel Mini

Fuel Drain

Empty the Fuel Tank

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Wrong Fuel Drain Mini

System Flush

Clean out the fuel lines & pumps

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Petrol in Diesel Drain Mini

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.

Get in Touch

Should you have any queries or need our assistance please Contact Us!
We can get you on the road once again.

24 hour Mini Helpline

0333 366 0103

Our Business Office

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

Weekdays: 9am to 5pm

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