Incorrect fuel in your Mercedes CLS 300? Diesel in your Petrol Mercedes?

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Mercedes Fuel Drain


Filling up with Diesel in a Petrol Mercedes is a regularly occurring problem. And what you should do about it varies according to a variety of things. If you would like to know what you need to do about this then read on.
Listed below are the main variables to consider whenever deciding on whether to have it drained:

  1. Exactly how much Diesel did you put in to the Mercedes, keeping in mind that the fuel tank capacity of your Mercedes CLS 300 is probably about 80 litres?
    1. Hardly any Diesel, as little as 4 litres of Diesel in a Petrol CLS 300 will more often than not not really be a significant problem. Experience has proven to us that anything under 4 litres (approximately 5% of the entire fuel tank capacity) is in many instances capable of being sufficiently diluted through completely topping up the remainder of the tank with Petrol.
      It is very uncommon to find an automobile experiencing difficulties with below 5% incorrect fuel contamination. Do not forget that it is unusual - certainly not impossible to find. You can get a number of vehicles that won't endure any degree of fuel contamination whatsoever.
    2. Between 4 and 8 litres of Diesel in the Mercedes (from 5 to 10%) is a 50/50 condition. Our experience has shown us that as many drivers get away with it as those people who break down. Any time you are trying to decide whether or not to risk it and just top it up remember that it is the same thing as gambling all of it on black - you have a 50/50 chance of it working.
    3. Anything more than 8 litres of Diesel in your Petrol CLS 300 must promptly be removed because your probability of getting away with this quantity of contamination is almost certainly below one in 50 - really big odds.
  2. Put Diesel in a Petrol Mercedes and drove it: Have you observed any kind of performance problems ever since putting the wrong fuel in your CLS 300? In that case, have it drained no matter the volume of Diesel or the contamination percentage. Continuing to drive running an automobile that is already starting to suffer the effects of wrong fuel contamination will just bring about even more damage affecting your fuel system.
  3. Do you want peace of mind?
    Then get it drained. Regardless of the contamination ratio, there is inevitably some degree of risk resulting from operating a Petrol engine on fuel contaminated with the wrong fuel. Probable consequences of driving on the incorrect fuel normally include the engine refusing to start, running lumpy, loss of power, degradation of the high-pressure pump, worn or bunged injectors, etc. These are a few of the most common Diesel in Petrol signs or symptoms, and in the event that you notice any of them then stop driving and have it removed right away.

Don't simply get any general so-and-so to attend your automobile. We are Mercedes experts and have got the certification and experience necessary to make certain that you are back on the road with a minimum of hassle or worry.

Put Diesel in a Petrol Mercedes

Inadvertently put Diesel in a Petrol Mercedes? Or possibly even put contaminated fuel in your Mercedes CLS 300?

Contact us for Help & Advice

Contact us and receive sincere recommendations and sensible assistance for your specific situation

We show up and drain it

We are able to reach you to perform the complete contaminated fuel drain & clean right there on scene

Once done You Get Moving Once again

When we have finished you will be able to get back on your way and get on with your trip

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain authorities in the UK, boasting national service, for Mercedes motorists in particular. We primarily fix:

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

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

The Process

The technique of removing Diesel from a Petrol vehicle is in essence identical for the vast majority of vehicle makes. As you can imagine it may vary to some degree as every make has their own fuel system. Even so it still essentially adheres to the below points:

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

In case you have any questions or need some help please Contact Us!
We are able to get you going once again.

24/7 Mercedes Helpline

0333 366 0103

Our Business Office

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

Weekdays: 9am to 5pm

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