Incorrect fuel in a BMW 740i? Diesel in your Petrol BMW?

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BMW Fuel Drain


Putting Diesel in a Petrol BMW is a usual problem. And its solution is dependent upon a number of factors. If perhaps you would like to find out what you must do about it then please read on.
Listed here are the most important variables to take into consideration when making a decision whether or not to have your car drained:

  1. What amount of Diesel have you put in the BMW, considering that the fuel tank capacity of the BMW 740i is probably around 95 litres?
    1. A modest amount of Diesel, something like 4.75 litres of Diesel in a Petrol 740i will generally not necessarily be a major problem. Experience has proven to us that an amount under 4.75 litres (which is 5% of the whole fuel tank) is in many instances able to be sufficiently diluted by means of wholly filling the rest of the tank with Petrol.
      It's very rare to come across a motor vehicle going through difficulties because of lower than 5% incorrect fuel contamination. Remember that it is uncommon - definitely not impossible to find. You can get a few vehicles that will not endure any level of contamination at all.
    2. Somewhere between 4.75 and 9.5 litres of Diesel in the BMW (from 5 to 10%) is a 50/50 condition. Our expertise has shown us that as many people get away with this as all those who don't. Any time you are deciding on whether or not to risk it and just simply fill it up bear in mind that it is just like betting it all on black - you will have a 50/50 chance of it being ok.
    3. Anything more than 9.5 litres of Diesel in a Petrol 740i ought to as soon as possible be drained seeing as your probability of succeeding with that level of contamination is probably less than one in 50 - really long odds.
  2. Put Diesel in a Petrol BMW and drove it: Have you noticed any performance problems after putting the bad fuel in the 740i? If you have, get it emptied regardless of the quantity of Diesel or even the contamination percentage. Continuing to run driving a vehicle that is now starting to suffer from the effects of fuel contamination will probably typically result in increasing amounts of harm being done to the fuel system components.
  3. Are you interested in reassurance?
    Then simply just get it drained. Regardless of the contamination ratio, there is invariably a certain level of danger caused by running a Petrol vehicle on Petrol contaminated with the wrong fuel. Probable results of driving on the incorrect fuel can include the motor refusing to start, running unevenly, lack of power, wearing of the high-pressure pump, worn out or blocked injectors, and so forth. These are some of the most common Diesel in Petrol signs or symptoms, and if you recognise any of them stop and have it removed right away.

Keep away from having any unqualified mechanic to try to fix your car. We are BMW specialists and have the qualifications and experience needed to ensure you get back on the road with minimum hassle or worry.

Put Diesel in a Petrol BMW

Accidentally put Diesel in a Petrol BMW? Or even put contaminated fuel in your BMW 740i?

Call us for Help & Advice

Contact us and receive reliable advice and sensible assistance for your exact circumstance

We come out and do the fuel drain

We would go to you to carry out the complete fuel drain & cleanse right there on scene

Once done You Get Going Again

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

Wrong Fuel Drain Specialists

We are the top rated wrong fuel drain specialists in the UK, having countrywide cover, for BMW motorists particularly. We predominantly attend:

  • Unleaded petrol in a Diesel Car
  • Diesel in your Unleaded Petrol Vehicle
  • AdBlue contamination
  • Water contamination

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

The Process

The technique of draining Diesel from a Petrol car is generally similar for virtually all vehicles. Needless to say it may vary to some degree as each make has their unique different fuel system. However it still observes 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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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.

Contact Us

In the event that you have any concerns or need help please Call us!
We can get you going once again.

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0333 366 0103

Our Corporate Office

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

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