Incorrect fuel in a BMW 125i? Diesel in a Petrol BMW?

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BMW Fuel Drain


Putting Diesel in a Petrol BMW is a very common problem. And what you have to do about it depends on several different factors. Assuming you want to know what you need to do about it then continue reading.
Right here are the most crucial variables to take into consideration whenever deciding on whether to get a fuel drain:

  1. Exactly how much Diesel did you put into the BMW, taking into account that the fuel capacity of the BMW 125i is usually about 52 litres?
    1. Hardly any Diesel, less than 2.6 litres of Diesel in a Petrol 125i will typically not be a major problem. Experience has taught us that anything less than 2.6 litres (which is roughly 5% of the fuel tank capacity) is frequently able to be completely diluted by wholly topping the tank with Petrol.
      It's highly unusual to find a car experiencing problems with below 5% wrong fuel contamination. Remember that it's infrequently found - not impossible to encounter. You can get a few motor vehicles that won't endure any amount of fuel contamination at all.
    2. In between 2.6 and 5.2 litres of Diesel in the BMW (from 5 to 10%) is really a 50/50 condition. Our experience has confirmed that as many motorists get away with it as those who break down. When deciding whether to chance it and just fill it up remember that it is the same thing as gambling everything on black - you've got a 50/50 chance of it being ok.
    3. Anything above 5.2 litres of Diesel in your Petrol 125i must right away be drained out because your probability of driving with that amount of contamination is probably lower than one in fifty - truly big odds.
  2. Put Diesel in a Petrol BMW and drove it: Have you seen any performance troubles since putting the bad fuel in the 125i? If so, get it drained regardless of the amount of Diesel or the contamination percentage. Proceeding to drive driving an automobile that is already beginning to suffer the effect of fuel contamination will definitely lead to even more damage affecting the fuel system parts.
  3. Would you like reassurance?
    Then simply just get it emptied. Regardless of contamination ratio, there is invariably a certain level of risk connected to operating a Petrol vehicle on Petrol contaminated with Diesel. Likely implications of driving a car on the wrong fuel can include the engine not starting, running unevenly, loss in power, wearing of the high-pressure pump, worn or bunged injectors, and so forth. These are several of the most common Diesel in Petrol signs and symptoms, and should you detect any of them then cease driving and get it drained immediately.

Stay away from having any jack-of-all-trades to try to drain your vehicle. We are BMW specialists and have got the skills and practical experience needed to ensure you are back on the road with a minimum of hassle or trouble.

Put Diesel in a Petrol BMW

Mistakenly put Diesel in a Petrol BMW? Or even put contaminated fuel in your BMW 125i?

Call us for Help & Guidance

Give us a call and get genuine recommendations and sensible assistance for your precise circumstance

We show up and drain it

We would come to you to do the full fuel removal & purge right there on scene

All done & You Get Moving Once again

Once we are done you are able to get back on the road and get on with your day

Wrong Fuel Drain Specialists

We are the primary wrong fuel drain authorities in the UK, boasting national cover, for BMW motorists particularly. We mainly attend to:

  • Unleaded petrol in Diesel Vehicle
  • Diesel in an Unleaded Petrol Vehicle
  • AdBlue contamination
  • Water fuel contamination

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

The Procedure

The system of draining Diesel from a Petrol car is essentially identical for most vehicle makes. As you can imagine it can differ to some extent as every brand has their particular fuel system. Having said that it still essentially follows 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 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.

Call us

In case you have any enquiries or want some help please Contact 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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