Wrong fuel in your Mercedes R350 CDI? Petrol in your Diesel Mercedes?

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Mercedes Fuel Drain


Putting Petrol in a Diesel Mercedes is a regularly occurring mistake. And its solution is determined by several things. If perhaps you would like to find out what you should do about it then stay with me.
These are the most crucial factors to keep in mind when deciding on whether or not to get a fuel drain:

  1. What level of Petrol did you put in to the Mercedes, taking into consideration that the fuel capacity of the Mercedes R350 CDI is in most cases about 80 litres?
    1. A small quantity of Petrol, less than 4 litres of Petrol in a Diesel R350 CDI will most of the time not necessarily be a massive problem. Experience has proven to us that an amount less than 4 litres (which is close to 5% of the fuel tank) is generally capable of being completely diluted by means of thoroughly filling up the remainder of the tank with the right fuel.
      It's pretty rare to encounter a motor vehicle suffering from problems with less than 5% incorrect fuel contamination. Keep in mind that it's unusual - definitely not impossible to encounter. You will discover some cars that will not stand any degree of contamination whatsoever.
    2. Somewhere between 4 and 8 litres of Petrol in the Mercedes (5 to 10%) is more of a 50/50 situation. Our practical experience has proven that as many people get away with this as all those who break down. When deciding on whether to chance it and simply fill it up remember that it is the same thing as wagering your car on black - you have got a 50/50 chance of it working out.
    3. Anything over 8 litres of Petrol in your Diesel R350 CDI must straightaway be drained since your likelihood of driving with that level of contamination is in all likelihood less than one in 50 - extremely big odds.
  2. Put Petrol in a Diesel Mercedes and drove it: Have you noticed any performance concerns since putting the bad fuel in the R350 CDI? If you have, have it removed no matter the volume of Petrol or even the contamination percentage. Continually running a vehicle that is now starting to suffer the effects of wrong fuel contamination will probably just be responsible for more harm being done to the fuel system components.
  3. Do you need assurance?
    You should get it emptied. Whatever the contamination percentage, there is inevitably some extent of risk linked with operating a Diesel vehicle on Diesel contaminated with Petrol. Likely consequences of driving a car on the wrong fuel include things like the engine not starting, running lumpy, reduced power, wearing of the high-pressure pump, worn or blocked injectors, and so on. These are several of the most frequently seen Petrol in Diesel warning signs, and should you notice any of them stop and get it drained immediately.

Do not just get any unqualified mechanic to attend your automobile. We are Mercedes experts and have got the accreditation and practical experience needed to make certain that you get back on the road with minimal hassle or worry.

Put Petrol in a Diesel Mercedes

Mistakenly put Petrol in a Diesel Mercedes? Or even put contaminated fuel in your Mercedes R350 CDI?

Give us a call for Assistance & Guidance

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

We arrive and do a fuel drain

We can reach you to do the full fuel drain & flush right there on scene

Once completed You Get Going Again

When we have finished you are able to get back on your way and get on with your day

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain experts in the UK, offering national coverage, for Mercedes motorists in particular. We mainly attend:

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

We are Mercedes specialists and have successfully drained thousands of Diesel Mercedes vehicles. Whether or not it is at the roadside, on a filling station forecourt, or even at home, we are able to get you on the road again.

The Process

The process of removing Petrol from a Diesel vehicle is in essence exactly the same for the majority of vehicles. Of course it can vary somewhat as every manufacturer has their particular distinct fuel system. However it still basically observes 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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Petrol in Diesel Questions

When someone has put Petrol in a Diesel car they have a few very common questions. So we have compiled a list of the most Frequently Asked Questions for you

I put Petrol in a Diesel 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 Diesel car on Petrol 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 Petrol can I get away with in a Diesel 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 Diesel 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.

Contact Us

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

24 hour 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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