But it was Asda that was recently left red-faced after doing this in its storage tanks, causing damage to customers’ cars.
It’s thought that more than 150,000 motorists pump the wrong kind of fuel into their car engines every year.
Why does it happen?
Asda’s fuel faux pas
When a supermarket giant says it’s not just sorry, but “incredibly sorry”, you know that there must have been a major slip-up. Well, that’s exactly how it was after Asda closed its Small Heath forecourt in Birmingham on 17th October.
Asda admitted: “We put the wrong fuels in the wrong tanks.” It meant that drivers using four of its pumps couldn’t help but put diesel into their petrol tanks or petrol into their diesel ones.
Asda has not revealed how many motorists were affected, but what we do know is that customers reported problems with their cars to the supermarket and the fault was identified at 1pm the next afternoon.
The supermarket blames a supplier and “human error”, saying it was a one-off. It is asking drivers affected to get in touch.
The damage it does
Petrol in a diesel tank will act like a solvent. Lubrication will be reduced, meaning that metal will grind on metal and potentially damage your pump.
This in turn can spread metal particles in your fuel, causing further havoc. Diesel in a petrol tank will potentially block up your fuel system and sparkplugs, causing your car to misfire and produce smoke. It might even break down.
What you can do about it
In the very worst cases, you may need to get a new engine fitted, but there are some steps you can take to reduce the damage:
But it doesn’t have to come to this. Remember – it only takes a couple of seconds to choose the correct pump. Just a little concentration can save a lot of money in the long run. So stay focused!