Contaminated fuel in your Mercedes E420? Diesel in a Petrol Mercedes?

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Mercedes Fuel Drain


Putting Diesel in a Petrol Mercedes is a regular mistake to make. And exactly what you have to do about it varies according to several different factors. Assuming you want to know what it is best to do about it then stay with me.
Let us discuss the key factors to to consider whenever determining whether to get a fuel drain:

  1. Exactly how much Diesel did you put in to the Mercedes, considering that the fuel capacity of your Mercedes E420 is normally roughly 80 litres?
    1. Hardly any Diesel, less than 4 litres of Diesel in a Petrol E420 will in most situations not really be a huge problem. Experience has taught us that anything less than 4 litres (which is about 5% of the whole fuel tank) is quite often able to be sufficiently diluted simply by completely topping up the rest of the tank with the right fuel.
      It is highly uncommon to come across a car or truck having issues because of lower than 5% wrong fuel contamination. Keep in mind it is very infrequently found - in no way impossible to encounter. There are certain automobiles that won't endure any level of fuel contamination in the slightest.
    2. Somewhere between 4 and 8 litres of Diesel in the Mercedes (5 to 10%) is more of a 50/50 scenario. Our practical experience has demonstrated that as many motorists get away with this as all those who break down. Whenever you are deciding upon whether to chance it and simply top it up recognise that it is very much like betting everything on black - you've got a 50/50 possibility of it working.
    3. Anything above 8 litres of Diesel in a Petrol E420 should right away be removed seeing that your likelihood of getting away with this amount of contamination is very likely lower than one in 50 - seriously long odds.
  2. Put Diesel in a Petrol Mercedes and drove it: Have you noted any performance issues after putting the incorrect fuel in your E420? If so, get it removed regardless of the quantity of Diesel or the contamination ratio. Continually running a vehicle that is already starting to suffer from the effects of fuel contamination will typically be responsible for progressively more damage affecting the fuel system parts.
  3. Are you interested in peace of mind?
    Then simply just get it emptied. Regardless of the contamination ratio, there is invariably some amount of risk connected with driving a Petrol vehicle on Petrol contaminated with Diesel. Possible final outcomes of driving on the incorrect fuel include things like the engine not starting, running lumpy, lack of power, degradation of the high-pressure pump, damaged or clogged injectors, etc. These are some of the most frequently seen Diesel in Petrol signs or symptoms, and in the event that you notice any of them then stop and get it removed immediately.

Don't simply get any general so-and-so to attend your car. We are Mercedes experts and hold the qualifications and working experience required to make sure that you are back on the road with no hassle or worry.

Put Diesel in a Petrol Mercedes

Mistakenly put Diesel in a Petrol Mercedes? Or possibly even put contaminated fuel in your Mercedes E420?

Contact us for Help & Guidance

Call us and receive straightforward recommendations and practical assistance for your exact circumstance

We show up and do a fuel drain

We would reach you to carry out the complete contaminated fuel retrieval & purge right there on scene

Once done You Get Going Once again

Once we have completed you are able to get back moving and get on with your trip

Wrong Fuel Drain Specialists

We are the top rated wrong fuel drain specialists in the UK, offering countrywide cover, for Mercedes motorists especially. We mainly fix:

  • Unleaded petrol in your Diesel Car
  • Diesel in an Unleaded Petrol Vehicle
  • 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 petrol station forecourt, or even at home, we are able to get you moving once again.

The Procedure

The system of getting rid of Diesel from a Petrol vehicle is essentially identical for most cars. As you can imagine it may differ to some extent as each make has their own different fuel system. Nevertheless it still generally follows the following principles:

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

In the event that you have any questions or want our assistance please Call us!
We can get you on the road 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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