Incorrect fuel in your BMW 740d? Petrol in your Diesel BMW?

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BMW Fuel Drain


Filling up with Petrol in a Diesel BMW is a fairly typical problem. And what you need to do about it depends on a few things. If you want to know what you ought to do to sort it out then keep on reading.
Here are the main factors to consider whenever making a decision whether to have it drained:

  1. What amount of Petrol have you put in the BMW, keeping in mind that the fuel capacity of your BMW 740d is most likely around 85 litres?
    1. Hardly any Petrol, as little as 4.25 litres of Petrol in a Diesel 740d will most of the time not really be a major problem. Experience has shown us that anything less than 4.25 litres (close to 5% of the whole fuel tank) is oftentimes able to be sufficiently diluted simply by thoroughly topping up the rest of the tank with Diesel.
      It is rather unusual to find a vehicle experiencing issues with under 5% incorrect fuel contamination. Bear in mind that it is infrequently found - certainly not impossible to find. There are a number of automobiles that don't endure any amount of fuel contamination in the slightest.
    2. Somewhere between 4.25 and 8.5 litres of Petrol in the BMW (5 to 10%) is really a 50/50 situation. Our practical experience demonstrates that as many people get away with this as all those who don't. Whenever you are figuring out whether or not to risk it and basically fill it up bear in mind that it is much like wagering all of it on black - you have a 50/50 possibility of it working.
    3. Anything more than 8.5 litres of Petrol in a Diesel 740d should really promptly be drained because your probability of succeeding with this quantity of contamination is more than likely below one in 50 - genuinely big odds.
  2. Put Petrol in a Diesel BMW and drove it: Have you noticed any kind of performance issues as a result of putting the bad fuel in the 740d? If you have, get it drained no matter the amount of Petrol or the contamination ratio. Still running a car that is now starting to suffer from the consequences of wrong fuel contamination will probably definitely be responsible for progressively more damage affecting your fuel system components.
  3. Are you looking for security?
    Then simply just get it drained. Whatever the contamination percentage, there is always some extent of risk connected with running a Diesel vehicle on fuel contaminated with Petrol. Possible consequences of driving a car on the wrong fuel can include the motor refusing to start, running lumpy, losing power, degradation of the high-pressure pump, damaged or bunged injectors, and the like. These are some of the most frequently seen Petrol in Diesel signs or symptoms, and if you notice any of them stop and have it removed immediately.

Do not just have any untrained so-and-so to attend your car. We are BMW specialists and hold the certification and working experience required to make certain that you get back on the road with minimum hassle or trouble.

Put Petrol in a Diesel BMW

Mistakenly put Petrol in a Diesel BMW? Or even put contaminated fuel in your BMW 740d?

Contact us for Help & Recommendations

Give us a call and receive straightforward advice and practical assistance for your precise circumstance

We arrive and drain it

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

Once done You Get Going Once again

When we have finished you will be able to get back on the road and get on with your day

Wrong Fuel Drain Specialists

We are the top rated wrong fuel drain professionals in the UK, offering nationwide service, for BMW motorists in particular. We principally deal with:

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

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

The Process

The technique of extracting Petrol from a Diesel car is essentially identical for most vehicle makes. Of course it can vary a bit as every manufacturer has their particular fuel system. Nevertheless it still fundamentally follows the below 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 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.

Call us

In the event that you have any queries or want some help please Call us!
We can get you moving 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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