Wrong fuel in a BMW M135i xDrive? Diesel in a Petrol BMW?

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BMW Fuel Drain


Filling Diesel in a Petrol BMW is a regular mistake. And exactly what you have to do about it varies according to several different factors. In case you want to find out what you should do about it then keep reading.
Here are the most important variables to take into account when choosing whether or not to get it drained:

  1. What level of Diesel did you put in the BMW, taking into consideration that the fuel tank capacity of the BMW M135i xDrive is usually roughly 52 litres?
    1. A small amount of Diesel, as little as 2.6 litres of Diesel in a Petrol M135i xDrive will quite often not necessarily be a big problem. Experience has shown us that an amount under 2.6 litres (about 5% of the total fuel tank) is generally able to be completely diluted by completely topping the tank with the correct fuel.
      It's rather rare to come across a car having issues due to less than 5% wrong fuel contamination. Be aware that it's rare - certainly not impossible to find. There are a number of vehicles that will not stand any level of contamination whatsoever.
    2. In between 2.6 and 5.2 litres of Diesel in the BMW (5 to 10%) is really a 50/50 scenario. Our working experience has shown that as many motorists get away with it as all those who don't. When figuring out whether or not to chance it and basically fill it up consider that it is the same as betting all of it on black - you have got a 50/50 possibility of it working out.
    3. Anything over 5.2 litres of Diesel in a Petrol M135i xDrive really should straight away be drained out since your probability of getting away with that quantity of contamination is undoubtedly less than one in 50 - really long odds.
  2. Put some Diesel in a Petrol BMW and drove it: Have you detected any kind of performance concerns ever since putting the bad fuel in your M135i xDrive? If you have, get it drained regardless of the amount of Diesel or the contamination ratio. Still running a vehicle that is currently beginning to suffer from the effects of fuel contamination will probably typically lead to more and more harm being done to your fuel system components.
  3. Do you want reassurance?
    Then simply just get it drained. No matter the contamination ratio, there is inevitably some degree of threat in connection with operating a Petrol vehicle on fuel contaminated with Diesel. Likely implications of driving a car on the incorrect fuel can include the motor refusing to start, running lumpy, loss of power, wearing of the high-pressure pump, damaged or blocked injectors, etc. These are a few of the most frequently seen Diesel in Petrol signs and symptoms, and in the event that you detect any of them stop and have it drained immediately.

Do not just have any jack-of-all-trades to attend your vehicle. We are BMW experts and hold the qualifications and practical experience needed to make sure that you get back on the road with minimal hassle or trouble.

Put Diesel in a Petrol BMW

Mistakenly put Diesel in a Petrol BMW? Or even put contaminated fuel in your BMW M135i xDrive?

Call us for Assistance & Advice

Give us a call and obtain reliable advice and sensible help for your specific situation

We come out and do the fuel drain

We can come to you to perform the contaminated fuel drain & clean right there on scene

All done & You Get Going Once again

As soon as we are done you can get back on the road and get on with your trip

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain specialists in the UK, offering countrywide service, for BMW motorists especially. We predominantly fix:

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

We are BMW specialists and have successfully drained hundreds of Petrol BMW vehicles. Whether it is roadside, on a petrol station forecourt, or even at home, we are able to get you on the road again.

The Procedure

The procedure of extracting Diesel from a Petrol car is generally identical for most vehicle makes. Needless to say it can vary somewhat as every make has their own fuel system. Nevertheless it still basically observes the below principles:

Petrol in Diesel BMW

Fuel Drain

Empty the Fuel Tank

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Wrong Fuel Drain BMW

System Flush

Clean out the fuel lines & pumps

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Petrol in Diesel Drain BMW

Vehicle Restart

Get the car up and running again

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Diesel in Petrol Questions

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.

Call us

In the event that you have any concerns or require our assistance please Call us!
We can get you on the road again.

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0333 366 0103

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

Weekdays: 9am to 5pm

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