Bad fuel in your BMW 420d? Petrol in your Diesel BMW?

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BMW Fuel Drain


Filling Petrol in a Diesel BMW is a common mistake. And its remedy is based on several factors. Assuming you would like to find out what to do about this then continue reading.
Listed below are the main factors to to consider whenever figuring out whether or not to get a fuel drain:

  1. How much Petrol did you put in the BMW, keeping in mind that the fuel capacity of the BMW 420d is in most cases approximately 60 litres?
    1. A modest amount of Petrol, less than 3 litres of Petrol in a Diesel 420d will more often than not not really be a massive problem. Experience has taught us that quantities under 3 litres (which is roughly 5% of the entire fuel tank volume) is in many instances able to be adequately diluted by means of completely filling up the tank with Diesel.
      It's extremely uncommon to find a car or truck having issues because of below 5% incorrect fuel contamination. Do not forget that it is unusual - definitely not impossible to encounter. There are actually certain vehicles that will not stand any amount of fuel contamination at all.
    2. Anywhere between 3 and 6 litres of Petrol in the BMW (5 to 10%) is more of a 50/50 scenario. Our working experience has revealed that as many drivers get away with it as those who break down. When you are trying to decide whether or not to chance it and just simply fill it up bear in mind that it is exactly like gambling all of it on black - you have a 50/50 chance of it working.
    3. Anything in excess of 6 litres of Petrol in a Diesel 420d must immediately be drained out seeing as your likelihood of driving with that quantity of contamination is undoubtedly lower than one in fifty - genuinely huge odds.
  2. Put Petrol in a Diesel BMW and drove it: Have you seen any kind of performance problems after putting the wrong fuel in the 420d? If so, get it emptied regardless of the volume of Petrol or the contamination ratio. Proceeding to run running a vehicle that is already starting to suffer from the consequences of fuel contamination will typically lead to more and more damage being done to the fuel system parts.
  3. Do you need assurance?
    Then get it removed. No matter the contamination ratio, there is inevitably some amount of danger caused by operating a Diesel motor on fuel contaminated with the incorrect fuel. Likely implications of driving on the wrong fuel include things like the motor refusing to start, running unevenly, losing power, degradation of the high-pressure pump, worn or blocked injectors, and so on. These are several of the most typical Petrol in Diesel symptoms, and in the event that you notice any of them then stop and get it drained asap.

Do not just get any unqualified mechanic to attend your automobile. We are BMW specialists and possess the credentials and working experience required to make sure that you get back on the road with a minimum of hassle or trouble.

Put Petrol in a Diesel BMW

Inadvertently put Petrol in a Diesel BMW? Or even put contaminated fuel in your BMW 420d?

Contact us for Help & Advice

Contact us and receive honest advice and sensible help for your precise circumstance

We come out and do the fuel drain

We can go to you to do the complete fuel drain & cleanse right there on scene

All done & You Get Going Once again

Once we have completed you will be able to get back moving and get on with your day

Wrong Fuel Drain Specialists

We are the primary wrong fuel drain professionals in the UK, boasting countrywide cover, for BMW motorists especially. We principally attend to:

  • Unleaded petrol in Diesel Auto
  • Diesel in your Unleaded Petrol Vehicle
  • AdBlue fuel contamination
  • Water fuel 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 are able to get you moving again.

The Process

The method of draining Petrol from a Diesel car is essentially the same for a large number of motor vehicles. Of course it does vary slightly as every manufacturer has their particular distinct fuel system. Nevertheless it still generally adheres to the following points:

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.

Call us

Should you have any concerns or need assistance please Call us!
We can get you going again.

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0333 366 0103

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

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