Wrong fuel in a Mercedes S420? Diesel in your Petrol Mercedes?

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Mercedes Fuel Drain


Filling Diesel in a Petrol Mercedes is a well-known mistake to make. And exactly what you have to do about it varies according to a few things. Assuming you want to know what it is best to do about this then read on.
Let us discuss the most crucial factors to take into consideration whenever making a decision whether to have your car drained:

  1. How much Diesel have you put in the Mercedes, keeping in mind that the fuel capacity of your Mercedes S420 is most likely approximately 100 litres?
    1. A tiny quantity of Diesel, less than 5 litres of Diesel in a Petrol S420 will typically not necessarily be a significant problem. Experience has demonstrated to us that quantities under 5 litres (5% of the fuel tank) is in many instances capable of being sufficiently diluted by entirely topping up the tank with the right fuel.
      It's pretty rare to find a car having issues with less than 5% wrong fuel contamination. Do not forget that it is very infrequently found - in no way impossible to find. You will discover a few automobiles that don't endure any degree of contamination whatsoever.
    2. Anywhere between 5 and 10 litres of Diesel in the Mercedes (5 to 10%) is more of a 50/50 scenario. Our expertise has confirmed that as many drivers get away with it as all those who don't. When you are trying to decide whether to risk it and just fill it up remember that it is much like gambling your car on black - you will have a 50/50 possibility of it working.
    3. Anything above 10 litres of Diesel in a Petrol S420 must straightaway be drained out seeing as your probability of driving with this level of contamination is almost certainly less than one in fifty - definitely big odds.
  2. Put Diesel in a Petrol Mercedes and drove it: Have you noticed any performance troubles ever since putting the bad fuel in your S420? If you have, have it emptied no matter the volume of Diesel or the contamination ratio. Proceeding to drive driving a vehicle that is currently beginning to suffer the consequences of fuel contamination will probably definitely be responsible for more harm affecting your fuel system parts.
  3. Would you like assurance?
    Simply get it emptied. No matter the contamination percentage, there is inevitably some extent of risk associated with operating a Petrol vehicle on fuel contaminated with the incorrect fuel. Likely results of driving on the incorrect fuel normally include the motor not starting, running lumpy, loss of power, wearing of the high-pressure pump, damaged or bunged injectors, and the like. These are a few of the most common Diesel in Petrol signs and symptoms, and if you observe any of them then stop and have it drained right now.

Avoid getting any unqualified mechanic to try to drain your automobile. We are Mercedes specialists and have got the accreditation and working experience necessary to ensure that you are back on the road with minimum hassle or trouble.

Put Diesel in a Petrol Mercedes

Accidentally put Diesel in a Petrol Mercedes? Or perhaps even put contaminated fuel in your Mercedes S420?

Give us a call for Assistance & Advice

Give us a call and get genuine guidance and practical help for your particular circumstance

We come out and do a fuel drain

We can go to you to undertake the complete fuel retrieval & cleanse right there on scene

All done & You Get Going Again

As soon as we are done you can get back on your way and get on with your day

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain specialists in the UK, offering nationwide coverage, for Mercedes motorists in particular. We mostly attend:

  • Unleaded petrol in 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. Whether or not it's at the roadside, on a station forecourt, or even at your house, we are able to get you moving again.

The Procedure

The technique of extracting Diesel from a Petrol car is in essence identical for a large number of cars. Naturally it may differ a little as every make has their own distinct fuel system. Nevertheless it still basically observes 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 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.

Get in Touch

If you have any questions or want our help please Call us!
We can get you moving once again.

24/7 Mercedes Helpline

0333 366 0103

Our Corporate Office

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


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