Keeping you up to speed
It’s your worst nightmare; either first thing in the morning, bleary eyed and sleepy, or last thing at night, tired from a long day at work, you go to fill up and suddenly realise you’re putting in the wrong fuel. Of course, by the time you notice, it’s too late, and you won’t be able to pull that fuel back out of your car.
First thing to realise is that you are not alone. As many as 150,000 people a year, or one every five minutes, put the wrong fuel in their cars, or more likely the cars of their employer or friends that they are not used to.
So what happens if you put diesel in your petrol car or vice versa and what should you do?
It is unlikely that you will accidentally put diesel into a petrol car, as the diesel nozzle is usually too large to fit into a petrol tank opening.
Putting petrol in a diesel vehicle is much more common, especially if your vehicle runs so quietly that you forget that it is actually a diesel engine. Petrol in diesel engines is a disaster, as diesel engines use the heavier diesel fuel to lubricate as well as power their engines. Without lubrication, metal grinds against metal, not only causing cylinder damage but also creating metal shards that can go on to cause huge damage further on in the system. Modern HDi diesel engines can suffer massive damage if the wrong fuel is used.
The most important thing if you fill up with the wrong fuel is to stop straight away and do nothing else with your car.
Don’t even turn on the ignition as this often pumps fuel into the engine ready for start up. Most of the damage caused by wrong fuel is done when the engine is turned on; until then, all you have is a contaminated tank. Ignoring this essential piece of advice costs UK motorists an estimated £50m a year in repairs.
Some say that you can put up to 10% of the wrong fuel in and be ok, especially if you are able to fill up with the correct fuel to dilute your mistake, but you really shouldn’t risk it. Even if you have only put in a couple of litres before you realise your mistake, you should still seek expert advice before you do anything that could damage your vehicle.