Bad fuel in a BMW 635d? Petrol in your Diesel BMW?

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BMW Fuel Drain


Putting Petrol in a Diesel BMW is a common problem. And its remedy varies according to a few factors. In case you want to know what you must do about this then read on.
Listed below are the key factors to be aware of when making a decision whether or not to get a fuel drain:

  1. How much Petrol did you put in to the BMW, keeping in mind that the fuel capacity of your BMW 635d is normally about 70 litres?
    1. A small quantity of Petrol, less than 3.5 litres of Petrol in a Diesel 635d will typically not be a significant problem. Experience has taught us that quantities less than 3.5 litres (almost 5% of the fuel tank volume) is generally capable of being adequately diluted by means of wholly filling up the rest of the tank with the right fuel.
      It is pretty rare to come across a car suffering from difficulties with lower than 5% incorrect fuel contamination. Keep in mind that it is very uncommon - in no way impossible to find. There are actually some vehicles that will not endure any degree of fuel contamination whatsoever.
    2. Between 3.5 and 7 litres of Petrol in the BMW (5 to 10%) is really a 50/50 condition. Our practical experience has revealed that as many people get away with this as those who break down. Any time you're figuring out whether to chance it and basically fill it up consider that it is exactly like betting your car on black - you will have a 50/50 possibility of it being ok.
    3. Anything above 7 litres of Petrol in your Diesel 635d must straightaway be drained seeing as your probability of succeeding with that amount of contamination is undoubtedly lower than one in 50 - seriously huge odds.
  2. Put Petrol in a Diesel BMW and drove it: Have you spotted any kind of performance difficulties as a result of putting the wrong fuel in the 635d? If that's the case, have it removed irrespective of the volume of Petrol or the contamination percentage. Continuing to run running a car that is currently beginning to suffer from the consequences of wrong fuel contamination can just be responsible for even more harm affecting your fuel system.
  3. Are you looking for assurance?
    Then get it removed. Whatever the contamination ratio, there is invariably some amount of danger connected to operating a Diesel motor on fuel contaminated with the incorrect fuel. Probable outcomes of driving on the wrong fuel include the engine not starting, running lumpy, losing power, degradation of the high-pressure pump, worn or blocked injectors, and so forth. These are a few of the commonest Petrol in Diesel warning signs, and if you detect any of them stop and have it drained right now.

Keep away from getting any unqualified so-and-so to attend your automobile. We are BMW experts and hold the credentials and working experience necessary to make certain you are back on the road with minimal hassle or worry.

Put Petrol in a Diesel BMW

By mistake put Petrol in a Diesel BMW? Or even put contaminated fuel in your BMW 635d?

Give us a call for Assistance & Guidance

Call us and receive straightforward guidance and practical assistance for your exact circumstances

We show up and do a fuel drain

We are able to go to you to carry out the complete fuel drain & clean right there on scene

All done & You Get Moving Again

When we have completed you are able to get back on the road and get on with your day

Wrong Fuel Drain Specialists

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

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

We are BMW specialists and have successfully drained hundreds of Diesel BMW vehicles. No matter if it's roadside, on a station forecourt, or even at your house, we are able to get you going once again.

The Procedure

The technique of extracting Petrol from a Diesel car is in essence the same for virtually all cars. Of course it does vary to some degree as each make has their unique fuel system. Even so it still generally 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 FAQs

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 case you have any questions or need assistance please Contact Us!
We are able to get you going once 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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