Incorrect fuel in a BMW 735i? Diesel in a Petrol BMW?

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BMW Fuel Drain


Putting Diesel in a Petrol BMW is a very common error. And its remedy is determined by several different things. If perhaps you would like to find out what you should do to sort it out then keep reading.
These are the most crucial variables to keep in mind when figuring out whether or not to have the car drained:

  1. How much Diesel have you put into the BMW, considering that the fuel tank capacity of the BMW 735i is normally around 85 litres?
    1. A modest amount of Diesel, less than 4.25 litres of Diesel in a Petrol 735i will generally not necessarily be a significant problem. Experience has shown us that an amount less than 4.25 litres (close to 5% of the whole fuel tank capacity) is in many instances capable of being sufficiently diluted simply by thoroughly topping the remainder of the tank with Petrol.
      It's quite uncommon to come across a vehicle having issues with less than 5% incorrect fuel contamination. Keep in mind that it's unusual - certainly not impossible to encounter. There are actually some motor vehicles that won't endure any amount of fuel contamination whatsoever.
    2. In between 4.25 and 8.5 litres of Diesel in the BMW (5 to 10%) is a 50/50 scenario. Our practical experience has shown that as many people get away with it as those people who don't. Whenever you are deciding upon whether or not to risk it and just simply top it up remember that it is the same thing as betting it all on black - you've got a 50/50 possibility of it being ok.
    3. Anything above 8.5 litres of Diesel in your Petrol 735i really should promptly be removed seeing as your probability of getting away with that level of contamination is very likely less than one in 50 - truly long odds.
  2. Put Diesel in a Petrol BMW and drove it: Have you noticed any kind of performance difficulties after putting the wrong fuel in your 735i? If you have, have it removed irrespective of the amount of Diesel or even the contamination percentage. Proceeding to drive running an automobile that is starting to suffer from the effect of wrong fuel contamination will probably likely result in increasing amounts of damage affecting your fuel system components.
  3. Do you need peace of mind?
    You should get it removed. Regardless of the contamination ratio, there is invariably some degree of threat connected with driving a Petrol engine on Petrol contaminated with the wrong fuel. Possible consequences of driving a car on the incorrect fuel include the motor not starting, running unevenly, decrease in power, wearing of the high-pressure pump, damaged or bunged injectors, and so forth. These are several of the most common Diesel in Petrol warning signs, and in the event that you notice any of them stop and have it removed as soon as possible.

Avoid getting any jack-of-all-trades to try to drain your vehicle. We are BMW experts and have the accreditation and expertise necessary to ensure that you are back on the road with a minimum of hassle or worry.

Put Diesel in a Petrol BMW

By mistake put Diesel in a Petrol BMW? Or even put contaminated fuel in your BMW 735i?

Call us for Assistance & Advice

Call us and obtain genuine guidance and practical assistance for your specific circumstance

We show up and drain it

We are able to go to you to carry out the complete fuel removal & purge there on scene

All done & You Get Moving Again

When we have finished you will 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 authorities in the UK, offering nationwide cover, for BMW motorists especially. We mainly attend:

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

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

The Procedure

The technique of removing Diesel from a Petrol car is basically similar for virtually all cars. As you can imagine it does differ a bit as every manufacturer has their own different fuel system. Having said that it still adheres to the below 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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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

If you have any queries or require assistance please Contact Us!
We are able to get you on the road 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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