Bad fuel in your Mercedes S420 Coupe? Diesel in a Petrol Mercedes?

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Mercedes Fuel Drain


Filling up with Diesel in a Petrol Mercedes is a regular problem. And its solution is determined by a variety of factors. If perhaps you would like to know what you ought to do to sort it out then stay with me.
Listed here are the most important variables to be aware of when figuring out whether to get a fuel drain:

  1. Exactly how much Diesel have you put into the Mercedes, considering that the fuel tank capacity of your Mercedes S420 Coupe is in most cases approximately 100 litres?
    1. A small quantity of Diesel, as little as 5 litres of Diesel in a Petrol S420 Coupe will usually not be a major problem. Experience has taught us that quantities less than 5 litres (which is almost 5% of the total fuel tank capacity) is sometimes able to be sufficiently diluted by thoroughly topping up the remainder of the tank with the right fuel.
      It's quite unusual to find a car or truck experiencing issues with below 5% wrong fuel contamination. Please remember it is infrequent - in no way impossible to find. There are actually some vehicles that will not endure any degree of fuel contamination in the slightest.
    2. Between 5 and 10 litres of Diesel in the Mercedes (from 5 to 10%) is really a 50/50 scenario. Our practical experience has shown us that as many drivers get away with this as all those who break down. When you are trying to decide whether to chance it and simply fill it up consider that it is much like betting all of it on black - you've got a 50/50 chance of it working out.
    3. Anything above 10 litres of Diesel in a Petrol S420 Coupe must straightaway be drained because your probability of succeeding with that amount of contamination is almost certainly below one in 50 - genuinely huge odds.
  2. Put some Diesel in a Petrol Mercedes and drove it: Have you observed any performance concerns after putting the incorrect fuel in the S420 Coupe? If you have, have it drained irrespective of the quantity of Diesel or the contamination percentage. Continuing to drive running a vehicle that is now starting to suffer from the consequences of wrong fuel contamination will probably just bring about more damage affecting the fuel system.
  3. Do you need reassurance?
    Then simply just get it emptied. Regardless of the contamination percentage, there is inevitably some amount of danger connected to running a Petrol vehicle on Petrol contaminated with Diesel. Probable consequences of driving a vehicle on the incorrect fuel include the motor not starting, running unevenly, reduced power, degradation of the high-pressure pump, worn or clogged injectors, and so on. These are a few of the most common Diesel in Petrol signs and symptoms, and if you notice any of them then stop driving and get it removed right away.

Keep away from getting any unqualified so-and-so to try to fix your automobile. We are Mercedes specialists and possess the skills and knowledge required to ensure that you are back on the road with a minimum of 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 S420 Coupe?

Contact us for Help & Guidance

Give us a call and receive sincere advice and sensible help for your particular circumstances

We show up and drain it

We can come to you to undertake the complete contaminated fuel drain & purge right there on scene

Once completed You Get Going Again

As soon as we have finished you are able to get back on the road and get on with your trip

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain professionals in the UK, having nationwide cover, for Mercedes motorists particularly. We principally deal with:

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

We are Mercedes specialists and have successfully drained hundreds of Petrol Mercedes vehicles. Whether it is roadside, on a station forecourt, or even at home, we are able to get you moving once again.

The Process

The system of draining Diesel from a Petrol vehicle is fundamentally the same for a large number of vehicle makes. Obviously it does differ somewhat as every brand has their particular fuel system. Having said that it still fundamentally follows 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.

Get in Touch

If you have any queries or need some help please Contact Us!
We are able to get you going 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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