It’s a common sight in Singapore to see people shaking and tilting their car at petrol stations to get more fuel. But is the myth true? To investigate this, Steve Chia, the host of Talking Point, went on a mission to find out if this method actually helps drivers save some money.
Based on a video released on the Facebook page of ROADS.sg, it is said that this myth is untrue according an expert interviewed on the show.
Vincent Emmanuel Lee, who is the Director of Mister Garage, said that rocking your vehicle while pumping petrol doesn’t give you more fuel. He added “when we pump petrol into the tank, it creates foam and vapour, and that occupies the tank. So if you wait for the vapour and foam to dissipate, only then you can pump more petrol into the tank, and shaking the car doesn’t make the vapour dissipate faster.”
When asked on if shaking one’s car is damaging, Lee revealed that shaking the car is not bad, but overfilling the tank is as it causes the petrol to go into the evacuation system. This system helps to remove vapour from the fuel tank and the cost to repair it is very high.
Despite the explanation from the expert, many netizens still disagree with him, and Jun Kaii is one of them.
He states that as someone who only pumps when the fuel reserved light is on, he can get about 22.7 litres of petrol for $50 and that can cover 250km, which is about 11.3km/l. However, when he pumps petrol in Malaysia, he can get about 36-38 litres without rocking his car. But if he rocks, he can get a maximum of 42-43 litres, and he gets this amount when the fuel reserved light is off. With this amount, his car can run up to 480-520 km, which is about 11.9km/l. Therefore, he questioned the expert’s claim because he gets a much higher figure when he shakes his car.
According to him, car tanks are rectangular in shape and it creates air bubbles and foams when petrol is pumped into the tank. “Since we are not always on level ground, the bubbles floats somewhere at the top of the tank. So by pushing side by side or front and back, I’m trying to let the bubbles find its way to the tube where I pump. This released the air trapped inside and hence, I can pump more in,” he explained. He added that if this method is not working, people would not be doing “such silly things across the causeway”.
Another user named Xavier Moniaga also finds the expert’s claim untrue because he can pump an additional 20 litres into his Volkswagen Touareg when he shakes it.
Gaston Quek could get an additional 10-12 litres of petrol when he shakes his car, but if he don’t, then the petrol doesn’t budge even if he fills “to the brim”. He added that some petrol tanks are odd-shaped and by shaking it, you “get petrol into places which have air pockets and filling up the gaps that you don’t usually reach by pumping normally”.
So who is correct? Well, both are right in their own ways. Lee is correct to say that rocking your vehicle does not give you more fuel provided your fuel tank has a flat top where air is not trapped. As for those who shared their personal experiences of topping up fuel, if you look at the fuel tanks of their car model, you will realise that no matter how long you wait, the bubbles or foam will not dissipate due to the design of the fuel tank and the tank has to be tilted at an angle in order for the trapped air to escape.
So a car owner would have to check on his or her model’s fuel tank to decide whether or not, there is a need to shake the car for more fuel to be topped up in their next time to Johor Bahru.