Incorrect fuel in a Mazda 121 L? Diesel in a Petrol Mazda?

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Mazda Fuel Drain


Filling up with Diesel in a Petrol Mazda is a regular problem. And exactly what you want to do about it will depend on a few factors. If you want to know what you have to do to sort it out then keep on reading.
Here are the main variables to consider when determining whether to get a fuel drain:

  1. What amount of Diesel have you put in to the Mazda, taking into account that the fuel tank capacity of your Mazda 121 L is probably around 43 litres?
    1. A modest amount of Diesel, something like 2.15 litres of Diesel in a Petrol 121 L will in most cases not really be a massive problem. Experience has taught us that anything under 2.15 litres (which is about 5% of the overall fuel tank) is in many instances able to be sufficiently diluted by means of entirely topping up the remainder of the tank with the right fuel.
      It is pretty uncommon to encounter a car suffering from difficulties due to below 5% wrong fuel contamination. Bear in mind that it is infrequently found - not impossible to find. There are actually a few cars that will not endure any degree of contamination at all.
    2. Somewhere between 2.15 and 4.3 litres of Diesel in the Mazda (from 5 to 10%) is more of a 50/50 scenario. Our experience demonstrates that as many people get away with it as those who don't. Whenever you are trying to decide whether to chance it and basically fill it up consider that it is the same as betting it all on black - you have got a 50/50 possibility of it being ok.
    3. Anything more than 4.3 litres of Diesel in a Petrol 121 L should right away be drained since your probability of succeeding with this level of contamination is more than likely lower than one in fifty - definitely big odds.
  2. Put Diesel in a Petrol Mazda and drove it: Have you seen any kind of performance issues after putting the bad fuel in the 121 L? If that's the case, get it drained regardless of the amount of Diesel or the contamination ratio. Proceeding to drive running a vehicle that is already starting to suffer from the consequences of fuel contamination will only lead to more and more harm being caused to the fuel system parts.
  3. Do you want reassurance?
    Then simply just get it removed. Regardless of the contamination percentage, there is inevitably some amount of danger linked with running a Petrol motor on fuel contaminated with the incorrect fuel. Likely results of driving on the incorrect fuel include things like the motor not starting, running lumpy, reduced power, degradation of the high-pressure pump, damaged or clogged injectors, and so on. These are several of the most common Diesel in Petrol symptoms, and should you observe any of them cease driving and have it drained right now.

Do not simply have any unqualified so-and-so to try to drain your automobile. We are Mazda experts and have got the credentials and experience needed to make sure that you are back on the road with little hassle or worry.

Put Diesel in a Petrol Mazda

By mistake put Diesel in a Petrol Mazda? Or possibly even put contaminated fuel in your Mazda 121 L?

Call us for Help & Advice

Call us and get sincere guidance and practical assistance for your precise circumstances

We come out and do the fuel drain

We are able to come to you to perform the complete fuel drain & cleanse right there on scene

All done & You Get Moving Once again

Once we have completed you will be able to get back moving and get on with your day

Wrong Fuel Drain Specialists

We are the top rated wrong fuel drain experts in the UK, offering countrywide cover, for Mazda motorists in particular. We typically deal with:

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

We are Mazda specialists and have successfully drained hundreds of Petrol Mazda vehicles. Regardless of whether it's at the roadside, on a filling station forecourt, or even at home, we are able to get you going again.

The Procedure

The technique of extracting Diesel from a Petrol vehicle is basically similar for a large number of vehicle makes. Naturally it may vary to some degree as each make has their particular distinct fuel system. However it still basically observes the below points:

Petrol in Diesel Mazda

Fuel Drain

Empty the Fuel Tank

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Wrong Fuel Drain Mazda

System Flush

Clean out the fuel lines & pumps

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Petrol in Diesel Drain Mazda

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 assistance please Call us!
We can get you on the road again.

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0333 366 0103

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

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