Bad fuel in a BMW 525i? Diesel in your Petrol BMW?

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BMW Fuel Drain


Filling Diesel in a Petrol BMW is a usual mistake. And what you have to do about it hinges on a few factors. In case you want to know what you must do about this then keep on reading.
Here are the main variables to keep in mind when making a decision whether or not to have it drained:

  1. How much Diesel did you put in the BMW, keeping in mind that the fuel capacity of your BMW 525i is usually approximately 70 litres?
    1. A modest amount of Diesel, something like 3.5 litres of Diesel in a Petrol 525i will generally not really be a huge problem. Experience has taught us that anything under 3.5 litres (which is 5% of the whole fuel tank) is oftentimes capable of being adequately diluted by totally topping the remainder of the tank with Petrol.
      It's rather rare to come across an automobile going through issues with under 5% incorrect fuel contamination. Keep in mind it's unusual - in no way impossible to find. You can get some motor vehicles that will not endure any degree of contamination whatsoever.
    2. Between 3.5 and 7 litres of Diesel in the BMW (5 to 10%) is more of a 50/50 condition. Our working experience has proven that as many people get away with this as those people who don't. When trying to decide whether or not to chance it and just simply fill it up recognise that it is much like gambling your car on black - you have got a 50/50 chance of it being ok.
    3. Anything in excess of 7 litres of Diesel in a Petrol 525i should really right away be drained seeing that your probability of succeeding with that level of contamination is undoubtedly lower than one in 50 - seriously long odds.
  2. Put some Diesel in a Petrol BMW and drove it: Have you spotted any performance troubles since putting the bad fuel in your 525i? If that's the case, have it drained irrespective of the volume of Diesel or the contamination ratio. Continuing to run running a vehicle that is beginning to suffer the consequences of fuel contamination will likely result in increasing amounts of harm being done to the fuel system.
  3. Do you need peace of mind?
    You should get it emptied. Whatever the contamination ratio, there is invariably a certain level of danger linked with driving a Petrol engine on Petrol contaminated with the incorrect fuel. Likely consequences of driving on the wrong fuel can include the engine not starting, running unevenly, loss of power, degradation of the high-pressure pump, damaged or blocked injectors, and so on. These are several of the most common Diesel in Petrol symptoms, and should you detect any of them cease driving and have it removed right now.

Stay away from getting any jack-of-all-trades to try to fix your vehicle. We are BMW specialists and have got the certification and experience required to ensure you are back on the road with minimal hassle or worry.

Put Diesel in a Petrol BMW

By mistake put Diesel in a Petrol BMW? Or possibly even put contaminated fuel in your BMW 525i?

Give us a call for Help & Advice

Give us a call and obtain sincere advice and practical assistance for your specific situation

We arrive and do the fuel drain

We can reach you to perform the full fuel drain & clean right there on scene

Once completed You Get Going Once again

Once 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 leading wrong fuel drain professionals in the UK, offering national cover, for BMW motorists particularly. We principally attend to:

  • Unleaded petrol in a Diesel Vehicle
  • Diesel in Unleaded Petrol Auto
  • AdBlue contamination
  • Water contamination

We are BMW specialists and have successfully drained hundreds of Petrol BMW vehicles. Whether or not it is at the roadside, on a petrol station forecourt, or even at your house, we are able to get you moving once again.

The Procedure

The method of extracting Diesel from a Petrol car is fundamentally similar for most cars. Obviously it can vary somewhat as every brand has their particular different fuel system. Having said that it still fundamentally 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.

Contact Us

In case you have any queries or require our assistance please Contact Us!
We can get you moving 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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