Bad fuel in a BMW 640i? Diesel in your Petrol BMW?

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BMW Fuel Drain


Putting Diesel in a Petrol BMW is a regular error. And its remedy depends upon several things. Assuming you would like to know what to do to sort it out then keep reading.
Listed below are the most important factors to consider when choosing whether to have it drained:

  1. Exactly how much Diesel have you put in the BMW, considering that the fuel capacity of your BMW 640i is usually approximately 70 litres?
    1. A tiny quantity of Diesel, something like 3.5 litres of Diesel in a Petrol 640i will in most situations not be a significant problem. Experience has shown us that anything under 3.5 litres (which is 5% of the fuel tank capacity) is frequently able to be completely diluted simply by completely topping up the tank with Petrol.
      It is extremely unusual to come across an automobile having issues due to under 5% wrong fuel contamination. Keep in mind that it is uncommon - definitely not impossible to find. There are a number of automobiles that won't endure any level of fuel contamination whatsoever.
    2. Anywhere between 3.5 and 7 litres of Diesel in the BMW (from 5 to 10%) is more of a 50/50 situation. Our experience demonstrates that as many drivers get away with it as those people who break down. Any time you're deciding whether to chance it and simply top it up remember that it is much like gambling it all on black - you have a 50/50 chance of it being ok.
    3. Anything in excess of 7 litres of Diesel in a Petrol 640i should straightaway be drained out seeing that your likelihood of succeeding with that level of contamination is more than likely lower than one in 50 - genuinely big odds.
  2. Put some Diesel in a Petrol BMW and drove it: Have you spotted any performance troubles after putting the wrong fuel in your 640i? If that's the case, have it emptied irrespective of the amount of Diesel or the contamination percentage. Still running a motor vehicle that is currently beginning to suffer from the effect of fuel contamination can only end up in increasing amounts of harm affecting the fuel system.
  3. Are you looking for peace of mind?
    In that case get it removed. Regardless of the contamination ratio, there is always some degree of risk caused by driving a Petrol engine on fuel contaminated with Diesel. Possible final outcomes of driving a car on the wrong fuel include the engine refusing to start, running lumpy, decrease in power, wearing of the high-pressure pump, damaged or bunged injectors, and so forth. These are several of the commonest Diesel in Petrol symptoms, and if you detect any of them then stop driving and get it drained asap.

Refrain from having any jack-of-all-trades to attend your car. We are BMW specialists and hold the skills and practical experience required to ensure that you get back on the road with minimal hassle or worry.

Put Diesel in a Petrol BMW

Mistakenly put Diesel in a Petrol BMW? Or possibly even put contaminated fuel in your BMW 640i?

Give us a call for Assistance & Guidance

Contact us and obtain sincere recommendations and sensible assistance for your particular circumstance

We arrive and drain it

We would go to you to carry out the full fuel retrieval & flush right there on scene

Once completed You Get Going Again

When we are done you should be able to get back on the road and get on with your trip

Wrong Fuel Drain Specialists

We are the primary wrong fuel drain experts in the UK, offering nationwide coverage, for BMW motorists particularly. We mainly fix:

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

We are BMW specialists and have successfully drained hundreds of Petrol BMW vehicles. Even if it's roadside, on a filling station forecourt, or even at your house, we are able to get you on the road again.

The Procedure

The procedure of getting rid of Diesel from a Petrol vehicle is essentially exactly the same for most cars. Needless to say it can differ to some degree as each make has their own fuel system. Even so it still adheres to the below principles:

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.

Call us

In case you have any concerns or require our assistance please Contact Us!
We are able to get you on the road again.

24 hour BMW Helpline

0333 366 0103

Our Corporate Office

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

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