Incorrect fuel in a BMW 520d? Petrol in a Diesel BMW?

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BMW Fuel Drain


Filling up with Petrol in a Diesel BMW is a regularly occurring error. And exactly what you should do about it depends on several different factors. If perhaps you want to know what to do about it then read on.
Let us discuss the key variables to consider when making a decision whether to have a fuel drain:

  1. How much Petrol have you put into the BMW, taking into account that the fuel tank capacity of your BMW 520d is normally around 70 litres?
    1. A small amount of Petrol, less than 3.5 litres of Petrol in a Diesel 520d will more often than not not be a huge problem. Experience has demonstrated to us that an amount under 3.5 litres (which is approximately 5% of the overall fuel tank volume) is frequently capable of being completely diluted simply by completely filling the remainder of the tank with Diesel.
      It is highly uncommon to come across a vehicle having issues due to under 5% wrong fuel contamination. Keep in mind that it is very infrequently found - in no way impossible to find. There are actually a number of vehicles that don't stand any degree of fuel contamination at all.
    2. Anywhere between 3.5 and 7 litres of Petrol in the BMW (from 5 to 10%) is more of a 50/50 scenario. Our working experience has shown that as many motorists get away with this as those who break down. Any time you're deciding upon whether or not to chance it and basically top it up recognise that it is exactly like wagering your car on black - you have got a 50/50 possibility of it being ok.
    3. Anything in excess of 7 litres of Petrol in a Diesel 520d should really immediately be drained since your likelihood of succeeding with this level of contamination is undoubtedly lower than one in fifty - seriously big odds.
  2. Put Petrol in a Diesel BMW and drove it: Have you noted any kind of performance issues as a result of putting the bad fuel in the 520d? If you have, have it drained no matter the amount of Petrol or the contamination percentage. Still running a vehicle that is starting to suffer from the effect of wrong fuel contamination will probably only cause increasing amounts of harm affecting your fuel system.
  3. Do you want security?
    Then simply just get it removed. Regardless of contamination ratio, there is inevitably a certain level of threat connected with driving a Diesel vehicle on Diesel contaminated with Petrol. Possible consequences of driving a vehicle on the incorrect fuel include things like the motor refusing to start, running lumpy, lack of power, wearing of the high-pressure pump, worn or blocked injectors, and the like. These are several of the most common Petrol in Diesel warning signs, and should you recognise any of them stop and get it drained as soon as possible.

Keep away from having any unqualified mechanic to attend your automobile. We are BMW specialists and hold the accreditation and knowledge necessary to ensure that you get back on the road with a minimum of hassle or trouble.

Put Petrol in a Diesel BMW

By mistake put Petrol in a Diesel BMW? Or possibly even put contaminated fuel in your BMW 520d?

Call us for Assistance & Guidance

Call us and get genuine advice and practical assistance for your exact circumstance

We show up and do the fuel drain

We can go to you to perform the complete contaminated fuel retrieval & clean there on scene

All done & You Get Going Again

When we have finished you should be able to get back moving and get on with your day

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain specialists in the UK, offering national service, for BMW motorists particularly. We mostly fix:

  • Unleaded petrol in Diesel Auto
  • Diesel in an Unleaded Petrol Vehicle
  • AdBlue contamination
  • Water contamination

We are BMW specialists and have successfully drained hundreds of Diesel BMW vehicles. Regardless of whether it is roadside, on a petrol station forecourt, or even at your house, we can get you moving once again.

The Process

The method of removing Petrol from a Diesel car is fundamentally similar for virtually all motor vehicles. Obviously it may differ to some degree as each manufacturer has their own distinct fuel system. Even so it still fundamentally observes the following guidelines:

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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Petrol in Diesel Questions

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

I put Petrol in a Diesel 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 Diesel car on Petrol 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 Petrol can I get away with in a Diesel 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 Diesel 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

In the event that you have any queries or require some assistance please Call us!
We can get you moving once again.

24/7 BMW Helpline

0333 366 0103

Our Corporate Office

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

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