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

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Smart Fuel Drain


Filling up with Diesel in a Petrol Smart is a very common problem. And exactly what you have to do about it is determined by several things. In case you would like to find out what you ought to do about it then read on.
Let us discuss the key variables to keep in mind whenever determining whether to get the car drained:

  1. What level of Diesel did you put into the Smart, taking into account that the fuel tank capacity of your Smart pure is probably roughly 22 litres?
    1. A tiny amount of Diesel, as little as 1.1 litres of Diesel in a Petrol pure will in most cases not necessarily be a major problem. Experience has demonstrated to us that anything less than 1.1 litres (close to 5% of the whole fuel tank capacity) is frequently capable of being sufficiently diluted by means of completely topping the rest of the tank with Petrol.
      It is highly unusual to find a vehicle having problems because of less than 5% wrong fuel contamination. Keep in mind that it's unusual - not impossible to find. You can get a few automobiles that won't stand any amount of contamination in the slightest.
    2. Anywhere between 1.1 and 2.2 litres of Diesel in the Smart (from 5 to 10%) is more of a 50/50 situation. Our experience has demonstrated that as many drivers get away with it as those who don't. Whenever you are deciding upon whether or not to chance it and basically fill it up recognise that it is much like betting it all on black - you have got a 50/50 possibility of it being ok.
    3. Anything in excess of 2.2 litres of Diesel in a Petrol pure must as soon as possible be drained since your probability of driving with that quantity of contamination is almost certainly less than one in fifty - definitely big odds.
  2. Put some Diesel in a Petrol Smart and drove it: Have you seen any kind of performance troubles as a result of putting the bad fuel in your pure? If that's the case, get it removed regardless of the amount of Diesel or even the contamination percentage. Still driving an automobile that is already starting to suffer the consequences of wrong fuel contamination will probably likely end up in more damage being done to your fuel system parts.
  3. Do you need security?
    You should get it drained. Regardless of the contamination ratio, there is inevitably some degree of threat connected with running a Petrol motor on fuel contaminated with the incorrect fuel. Likely consequences of driving a car on the wrong fuel can include the engine not starting, running lumpy, loss of power, degradation of the high-pressure pump, worn out or clogged injectors, etc. These are a few of the most frequently seen Diesel in Petrol signs or symptoms, and should you recognise any of them stop and have it drained asap.

Steer clear of having any general so-and-so to attend your vehicle. We are Smart experts and hold the credentials and knowledge required to make sure that you are back on the road with a minimum of hassle or trouble.

Put Diesel in a Petrol Smart

Inadvertently put Diesel in a Petrol Smart? Or possibly even put contaminated fuel in your Smart pure?

Call us for Help & Recommendations

Give us a call and obtain sincere guidance and practical help for your specific circumstances

We show up and do a fuel drain

We would go to you to perform the contaminated fuel drain & flush right there on scene

Once done You Get Moving Again

Once 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 authorities in the UK, having countrywide cover, for Smart motorists in particular. We primarily fix:

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

We are Smart specialists and have successfully drained thousands of Petrol Smart vehicles. Whether it is roadside, on a filling station forecourt, or even at your home, we can get you moving once again.

The Procedure

The process of extracting Diesel from a Petrol vehicle is essentially identical for virtually all cars. Obviously it does differ slightly as every brand has their own distinct fuel system. However it still essentially adheres to the following guidelines:

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.

Call us

Should you have any concerns or need assistance please Contact Us!
We are able to get you going again.

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0333 366 0103

Our Corporate Office

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


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