Bad fuel in a Mercedes SLK 250? Diesel in your Petrol Mercedes?

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Mercedes Fuel Drain


Filling up with Diesel in a Petrol Mercedes is a common mistake to make. And exactly what you need to do about it varies according to several different factors. If you want to find out what you should do about this then please read on.
Listed below are the most important variables to to consider whenever deciding on whether to have a fuel drain:

  1. Exactly how much Diesel did you put into the Mercedes, keeping in mind that the fuel tank capacity of your Mercedes SLK 250 is usually about 70 litres?
    1. A small amount of Diesel, something like 3.5 litres of Diesel in a Petrol SLK 250 will generally not necessarily be a massive problem. Experience has shown us that an amount under 3.5 litres (which is roughly 5% of the overall fuel tank volume) is sometimes capable of being completely diluted by entirely topping the tank with Petrol.
      It's rather uncommon to find an automobile going through difficulties because of under 5% wrong fuel contamination. Keep in mind it is unusual - not impossible to find. You will discover a number of cars that don't stand any degree of fuel contamination whatsoever.
    2. Between 3.5 and 7 litres of Diesel in the Mercedes (5 to 10%) is more of a 50/50 situation. Our expertise has shown that as many motorists get away with this as all those who break down. When you are deciding on whether or not to risk it and just top it up bear in mind that it is exactly like gambling it all on black - you have got a 50/50 possibility of it being ok.
    3. Anything over 7 litres of Diesel in a Petrol SLK 250 really should as soon as possible be drained as your likelihood of driving with that quantity of contamination is undoubtedly lower than one in fifty - seriously big odds.
  2. Put Diesel in a Petrol Mercedes and drove it: Have you detected any performance difficulties as a result of putting the bad fuel in the SLK 250? If you have, have it removed regardless of the amount of Diesel or even the contamination ratio. Continuing to drive running a motor vehicle that is currently beginning to suffer the effect of fuel contamination will just cause increasing amounts of harm affecting the fuel system parts.
  3. Do you need security?
    Then simply just get it drained. No matter the contamination percentage, there is invariably a certain level of risk resulting from operating a Petrol engine on Petrol contaminated with Diesel. Probable implications of driving a vehicle on the wrong fuel can include the engine not starting, running unevenly, reduced power, wearing of the high-pressure pump, worn out or clogged injectors, etc. These are several of the most frequently seen Diesel in Petrol signs or symptoms, and in the event that you recognise any of them then stop and have it removed as soon as possible.

Stay away from getting any unqualified mechanic to try to drain your automobile. We are Mercedes specialists and possess the skills and practical experience required to ensure that you get back on the road with little hassle or trouble.

Put Diesel in a Petrol Mercedes

Mistakenly put Diesel in a Petrol Mercedes? Or possibly even put contaminated fuel in your Mercedes SLK 250?

Call us for Help & Guidance

Give us a call and obtain genuine guidance and practical help for your specific circumstances

We arrive and drain it

We can go to you to do the complete fuel removal & flush there on scene

All done & You Get Moving Again

As soon as we are done you are 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, boasting nationwide cover, for Mercedes motorists in particular. We predominantly fix:

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

We are Mercedes specialists and have successfully drained thousands of Petrol Mercedes vehicles. Even if it is roadside, on a petrol station forecourt, or even at your home, we can get you on the road again.

The Process

The technique of draining Diesel from a Petrol car is in essence identical for the majority of cars. Naturally it may vary to some degree as every manufacturer has their unique distinct fuel system. However it still essentially adheres to the below guidelines:

Petrol in Diesel Mercedes

Fuel Drain

Empty the Fuel Tank

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Wrong Fuel Drain Mercedes

System Flush

Clean out the fuel lines & pumps

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Petrol in Diesel Drain Mercedes

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

Should you have any queries or want assistance please Call us!
We can get you on the road again.

24 hour Mercedes Helpline

0333 366 0103

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

Weekdays: 9am to 5pm

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