Wrong fuel in a Smart Forfour pure? Diesel in your Petrol Smart?

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Smart Fuel Drain


Filling up with Diesel in a Petrol Smart is a common mistake to make. And what you should do about it depends upon a number of factors. In case you want to know what you should do about this then read on.
Listed here are the key factors to be aware of when determining whether or not to get a fuel drain:

  1. What level of Diesel have you put into the Smart, considering that the fuel capacity of the Smart Forfour pure is probably about 47 litres?
    1. A modest quantity of Diesel, something like 2.35 litres of Diesel in a Petrol Forfour pure will in most cases not be a big problem. Experience has shown us that anything under 2.35 litres (almost 5% of the fuel tank capacity) is sometimes capable of being adequately diluted by wholly topping the tank with the appropriate fuel.
      It's relatively uncommon to come across a vehicle suffering from difficulties because of under 5% wrong fuel contamination. Keep in mind that it is uncommon - in no way impossible to find. You can get a number of cars that won't stand any degree of contamination at all.
    2. Anywhere between 2.35 and 4.7 litres of Diesel in the Smart (from 5 to 10%) is really a 50/50 situation. Our expertise has demonstrated that as many motorists get away with this as those who break down. Whenever deciding on whether to risk it and just simply fill it up remember that it is much like wagering your car on black - you have got a 50/50 chance of it being ok.
    3. Anything above 4.7 litres of Diesel in a Petrol Forfour pure really should promptly be drained as your likelihood of driving with that amount of contamination is in all likelihood below one in fifty - seriously big odds.
  2. Put some Diesel in a Petrol Smart and drove it: Have you seen any kind of performance problems since putting the incorrect fuel in your Forfour pure? If that's the case, have it removed regardless of the amount of Diesel or the contamination percentage. Continually driving a vehicle that is now starting to suffer from the consequences of wrong fuel contamination will just bring about progressively more damage affecting your fuel system parts.
  3. Would you like assurance?
    In that case get it emptied. No matter the contamination ratio, there is always a certain level of danger caused by operating a Petrol vehicle on Petrol contaminated with the incorrect fuel. Probable outcomes of driving on the incorrect fuel can include the motor refusing to start, running unevenly, decrease in power, wearing of the high-pressure pump, worn or clogged injectors, etc. These are some of the most common Diesel in Petrol signs or symptoms, and in the event that you detect any of them then stop driving and have it removed asap.

Refrain from having any general so-and-so to try to fix your vehicle. We are Smart experts and have the accreditation and practical experience necessary to ensure you are back on the road with no hassle or trouble.

Put Diesel in a Petrol Smart

Accidentally put Diesel in a Petrol Smart? Or even put contaminated fuel in your Smart Forfour pure?

Contact us for Assistance & Recommendations

Give us a call and receive genuine recommendations and practical assistance for your specific circumstances

We come out and drain it

We can go to you to carry out the fuel retrieval & flush there on scene

Once carried out You Get Moving Once again

When we have completed you can get back moving and get on with your trip

Wrong Fuel Drain Specialists

We are the leading wrong fuel drain experts in the UK, offering national coverage, for Smart motorists particularly. We predominantly attend to:

  • Unleaded petrol in Diesel Auto
  • Diesel in an Unleaded Petrol Vehicle
  • AdBlue contamination
  • Water contamination

We are Smart specialists and have successfully drained thousands of Petrol Smart vehicles. Regardless of whether it's roadside, on a station forecourt, or even at your house, we can get you on the road once again.

The Process

The technique of getting rid of Diesel from a Petrol vehicle is essentially exactly the same for the vast majority of vehicle makes. As you can imagine it does differ to some degree as each make has their particular distinct fuel system. Having said that it still basically adheres to the below points:

Petrol in Diesel Smart

Fuel Drain

Empty the Fuel Tank

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Wrong Fuel Drain Smart

System Flush

Clean out the fuel lines & pumps

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Petrol in Diesel Drain Smart

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

If you have any concerns or want some assistance please Call us!
We are able to get you on the road again.

24/7 Smart 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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