Bad fuel in a Mercedes CL420? Diesel in your Petrol Mercedes?

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Mercedes Fuel Drain


Putting Diesel in a Petrol Mercedes is a common error. And its solution is dependent upon several things. If perhaps you would like to know what you have to do to fix it then stay with me.
These are the key factors to think about when determining whether to get a fuel drain:

  1. How much Diesel did you put in to the Mercedes, keeping in mind that the fuel tank capacity of your Mercedes CL420 is normally around 100 litres?
    1. Hardly any Diesel, something like 5 litres of Diesel in a Petrol CL420 will usually not really be a significant problem. Experience has proven to us that anything under 5 litres (which is approximately 5% of the overall fuel tank volume) is sometimes capable of being completely diluted simply by totally topping the rest of the tank with the correct fuel.
      It's extremely unusual to find a car or truck having difficulties due to under 5% incorrect fuel contamination. Keep in mind that it is rare - certainly not impossible to find. You will discover certain vehicles that won't stand any quantity of contamination in the slightest.
    2. Anywhere between 5 and 10 litres of Diesel in the Mercedes (from 5 to 10%) is really a 50/50 condition. Our working experience has proven that as many drivers get away with this as those who break down. When you are deciding upon whether or not to risk it and basically top it up consider that it is the same as wagering everything on black - you have a 50/50 chance of it working.
    3. Anything over 10 litres of Diesel in your Petrol CL420 should straightaway be removed as your likelihood of driving with this level of contamination is very likely less than one in fifty - extremely huge odds.
  2. Put some Diesel in a Petrol Mercedes and drove it: Have you detected any kind of performance problems as a result of putting the wrong fuel in the CL420? In that case, get it emptied regardless of the quantity of Diesel or the contamination ratio. Still driving a motor vehicle that is currently beginning to suffer the consequences of wrong fuel contamination will definitely be responsible for even more damage affecting the fuel system.
  3. Are you interested in security?
    You should get it emptied. Whatever the contamination percentage, there is inevitably some amount of risk resulting from driving a Petrol engine on Petrol contaminated with the wrong fuel. Possible results of driving a car on the incorrect fuel include the engine not starting, running lumpy, loss of power, degradation of the high-pressure pump, damaged or bunged injectors, and so on. These are several of the most typical Diesel in Petrol signs and symptoms, and should you recognise any of them stop driving and get it removed right away.

Stay away from getting any jack-of-all-trades to attend your automobile. We are Mercedes specialists and possess the certification and working experience needed to make certain that you are back on the road with minimal hassle or trouble.

Put Diesel in a Petrol Mercedes

Unintentionally put Diesel in a Petrol Mercedes? Or even put contaminated fuel in your Mercedes CL420?

Call us for Assistance & Recommendations

Contact us and get sincere advice and practical help for your particular circumstances

We come out and do a fuel drain

We are able to reach you to do the full contaminated fuel retrieval & cleanse there on scene

Once performed You Get Moving Once again

As soon as we have finished 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, boasting countrywide cover, for Mercedes motorists especially. We primarily fix:

  • Unleaded petrol in Diesel Car
  • Diesel in your 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 station forecourt, or even at home, we are able to get you on the road once again.

The Procedure

The technique of removing Diesel from a Petrol car is fundamentally identical for the majority of vehicles. Obviously it may vary somewhat as every make has their own distinct fuel system. Having said that it still fundamentally 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 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.

Call us

Should you have any enquiries or want some assistance please Contact Us!
We are able to get you on the road once again.

24 hour Mercedes Helpline

0333 366 0103

Our Corporate Office

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

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