The misfuelling prevention device



The following FAQs should shed light on the topic of misfuels or misfuelling to allay any concerns you may have surrounding the issue of pumping petrol in a diesel vehicle’s tank.

What is “misfuelling”?

Simply put, misfuelling takes place when you pump petrol into the fuel tank of a diesel vehicle.

This can happen as the pump nozzle on a diesel pump has a larger diameter than an unleaded fuel nozzle and so the unleaded nozzle can easily fit into the filler neck of the diesel tank.

It only takes the slightest distraction for someone to make this error, and the consequences can be costly, anything from in the region of £200 to over £3000, depending on how much damage is done to your vehicle. The worst case scenario of course is that the entire fuel system needs replacing.

The worst thing you can do is drive off the forecourt once you have pumped petrol into your diesel vehicle. If you have left the fuel station, call your roadside assistance organisation and have your vehicle towed or transported to a garage where the fuel tank can be flushed of petrol and refilled with diesel. Please note, misfuelling is not normally covered under your roadside assistance agreement and the cost of draining your tank usually starts at about £175.00.

Thus, the Diesel Head Misfuel Prevention Device can save you a lot of money for a small upfront investment– fit and forget!

How frequently does it occur?

Misfuel numbers point to around 150,000 incidents a year in the UK alone, that is one every three and a half minutes. If it has just happened to you, you are certainly not alone.

Is it on the increase?

Sadly, yes. With car manufacturers slow to catch up, there are still millions of diesel tanks without an OEM misfuel prevention device such as Diesel Head installed.

Why is it on the increase?

One theory is two car families: with petrol and diesel vehicle sales remaining equal, a growing number of households have one of each so drivers are having to become used to filling from both pumps!

Misfuelling – Battle of the Sexes!

Research by recovery firm Green Flag actually shows men are more likely to misfuel than women but, whichever sex is in the dock, be prepared to dig deep to get the diesel vehicle fixed. If, having misfuelled, a motorist doesn’t start the engine, he or she may get away with just having the tank flushed. AA Fuel Assist will do this for £176.50 at the time of writing this. However, if the driver turns on the ignition, the sky may be the limit as the diesel engine and fuel system grind to a halt. That is without factoring in the cost of properly licensed disposal of the contaminated fuel. The AA alone disposes of around 20,000 litres a week.

Can you insure against it?

Yes, but at over £40 a year in terms of premiums, fitting a Diesel Head Misfuel Prevention Device is really more cost effective. Insurance can cover the funds but it cannot save you the grief, inconvenience and lost time that misfuelling causes, never mind the consequences of you not completing that particular trip on time!

Does it invalidate your warranty?

There is no doubt that engine and fuel system damage can be caused by running the wrong fuel, So if, as a result, your car is taken to a dealership with a view to claiming on the warranty for major component failure you may be in for a shock.

Why don’t people put diesel in petrol tanks?

Diesel misfuelling is easily done. An unleaded pump nozzle is smaller in diameter than a diesel nozzle and so fits the tank filler neck without resistance. However, the reverse does not apply as the diesel nozzle simply will not fit in the filler of an unleaded petrol tank.

Will running petrol through my engine damage it?

Diesel lubricates the engine. Petrol is a solvent and quickly removes any protection. Expensive, high-pressure fuel pumps can be stripped and metal pieces blasted throughout the system. Having to replace an engine is rare, but renewing the fuel system and injectors typically costs around £3,000.  The best approach is to resolve the issue of petrol in diesel by fitting a misfuel prevention gadget.

Does size matter?

Yes, of course. The standard Diesel Head Misfuel Prevention Device has been designed to offer strength and security via their robust engineering, while also features low profiles to fit precisely in as many vehicles as possible.