Contaminated fuel in a Smart Forfour cdi? Petrol in your Diesel Smart?

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Smart Fuel Drain


Putting Petrol in a Diesel Smart is a common mistake to make. And exactly what you should do about it is dependent upon a few factors. In the event that you want to find out what you need to do to sort it out then please read on.
Here are the most important factors to take into account whenever figuring out whether or not to get your car drained:

  1. Exactly how much Petrol did you put into the Smart, bearing in mind that the fuel capacity of the Smart Forfour cdi is most likely approximately 47 litres?
    1. A tiny amount of Petrol, something like 2.35 litres of Petrol in a Diesel Forfour cdi will quite often not really be a huge problem. Experience has taught us that quantities under 2.35 litres (close to 5% of the fuel tank) is oftentimes able to be adequately diluted by means of wholly filling the rest of the tank with the appropriate fuel.
      It is quite rare to find a car experiencing issues with under 5% wrong fuel contamination. Bear in mind that it's infrequent - definitely not impossible to find. There are actually some cars that won't stand any amount of contamination at all.
    2. Between 2.35 and 4.7 litres of Petrol in the Smart (5 to 10%) is a 50/50 situation. Our practical experience has shown that as many people get away with this as all those who break down. Whenever you are deciding on whether to risk it and just top it up remember that it is exactly like gambling all of it on black - you have a 50/50 chance of it working out.
    3. Anything above 4.7 litres of Petrol in a Diesel Forfour cdi must as soon as possible be drained out as your likelihood of succeeding with that level of contamination is more than likely below one in 50 - seriously huge odds.
  2. Put some Petrol in a Diesel Smart and drove it: Have you spotted any kind of performance problems as a result of putting the bad fuel in the Forfour cdi? If you have, have it removed no matter the volume of Petrol or even the contamination percentage. Continuing to drive driving a vehicle that is currently beginning to suffer from the consequences of wrong fuel contamination can just cause increasing amounts of damage being caused to the fuel system.
  3. Do you want assurance?
    Simply get it emptied. No matter the contamination percentage, there is always some degree of threat in connection with operating a Diesel engine on Diesel contaminated with Petrol. Likely implications of driving on the incorrect fuel include the engine refusing to start, running lumpy, loss in power, wearing of the high-pressure pump, worn out or blocked injectors, and so forth. These are some of the commonest Petrol in Diesel signs and symptoms, and in the event that you detect any of them cease driving and have it removed right away.

Avoid having any jack-of-all-trades to attend your vehicle. We are Smart experts and hold the skills and knowledge necessary to make certain that you get back on the road with minimum hassle or worry.

Put Petrol in a Diesel Smart

Unintentionally put Petrol in a Diesel Smart? Or possibly even put contaminated fuel in your Smart Forfour cdi?

Give us a call for Assistance & Recommendations

Give us a call and receive sincere recommendations and practical help for your particular circumstance

We come out and do the fuel drain

We would come to you to carry out the full contaminated fuel removal & flush right there on scene

Once performed You Get Moving Once again

As soon as we are done you should be able to get back moving and get on with your day

Wrong Fuel Drain Specialists

We are the primary wrong fuel drain specialists in the UK, boasting countrywide coverage, for Smart motorists in particular. We principally deal with:

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

We are Smart specialists and have successfully drained hundreds of Diesel Smart vehicles. Whether or not it is roadside, on a petrol station forecourt, or even at home, we are able to get you going once again.

The Process

The process of extracting Petrol from a Diesel vehicle is essentially identical for a large number of vehicles. Of course it does vary to some degree as each manufacturer has their particular different fuel system. Nevertheless it still fundamentally follows the below principles:

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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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.

Call us

In case you have any queries or require our help please Contact 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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