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Why you shouldn’t drive your car on low fuel

You could have problems more serious than just stalling

Do you regularly ignore your car’s fuel level? PHOTO BY VERNON B. SARNE

Due to the rising costs of oil production in the world market, the strengthening US dollar versus our peso, and the implementation of the TRAIN law, it seems fuel prices won’t be going down anytime soon. Opening your wallet to get a fill is more painful now than it has been in years.

In online car forums and chatrooms, I have noticed that a number of motorists are developing this habit of driving their cars all the way to a near-empty fuel tank. They even share photos of their alarmingly low fuel gauges and range. It may be amusing to see how far you can stretch those few liters you have left in the tank and how long you can put off having to hand over your gas money, but there’s a more serious downside to this practice besides merely looking like a complete idiot if you end up getting stalled in traffic and having to push your car to the nearest gas station. Allow me to explain.

The fuel delivery system requires care. PHOTO BY MANSKEE NASCIMENTO

We all know that the combustion process in your engine gives your vehicle the propulsion it needs. For combustion to occur, certain components have to work in unison. One crucial aspect is the fuel delivery system, which includes the injectors, the fuel line, the filter and the fuel pump. If one component of this system fails or clogs up, engine performance will be hindered or, worse, become completely inoperative.

Now, your vehicle’s fuel pump requires cooling to prolong its life. This is made possible by the fuel in your tank that goes straight into the pump. Modern direct-injection engines are equipped with high-pressure fuel pumps capable of outputs in four-digit psi figures, generating stress and heat on the pump itself, hence the need for cooling. Running your car with almost fumes left in its tank will deprive the pump of the cooling it needs. Do this often enough over a period of time and you’ll have your fuel pump fail on you.

Gas up before the fuel gauge warning lights up. PHOTO BY VERNON B. SARNE

Do note that symptoms of a failing pump may go unnoticed for a long time, and it would really suck if you get stranded on a dark highway in the middle of the night when it finally conks out on you. To give you an idea, the replacement for a fuel pump in my 2015 Mazda 3 costs P21,000 (labor not included). That is no joke.

Make it a rule to never go below the last-quarter marker on your fuel gauge, and you’ll never have to deal with expensive repairs and replacement due to neglect or ignorance. In addition, running on low fuel levels may introduce debris that has accumulated at the tank’s bottom into the fuel delivery system, causing premature filter replacement and possible clogging.

So, are you guilty of this practice?

Manskee Nascimento
