Ask the Mechanic: Why you should avoid an empty fuel tank


By Nelson Xavier Ssenyange

We have all been there and for many the fuel light can be the bane of owning a car, but whether it's just before pay day and money is tight or you simply forgot to fill up on your way past the petrol station, there are a number of reasons why you won’t want to run your car on empty. Today, we look at why you should always keep your car well topped up and what might happen if you don’t.

The easiest way to tell that your car is running with the tank on empty or nearly empty is from your car’s fuel light. But every car fuel light will illuminate at a different time so don’t use this as a steadfast guide. You should think twice about driving if you have less than a quarter of a tank in the car, many newer cars now have smart fuel gauges that also let you know the range you have left before your engine dies but even this may change depending on your speed and the kind of driving that you’re doing.

Why shouldn’t you run your car with a nearly empty fuel tank?

Running your car with a virtually empty fuel tank will sound ludicrous to many drivers, but unfortunately the number of roadside recoveries occurring as a result of running dry shows that this is a real problem in Uganda. Here are just a few reasons why you shouldn’t risk driving with low fuel:

1. Unreliable fuel light and gauge

If you are relying on your fuel gauge being accurate, leaving fuel to run low may be playing a risky game. Obviously, the newer the car the more accurate your fuel gauge should be, but drivers with older cars should never leave refilling to chance. A number of factors can affect what the fuel gauge reads, including whether you are just starting the car in the morning or if you’re on a particularly long drive. If you notice that your fuel gauge is acting inconsistent, then it may need a mechanic to repair the issue.

2. Low fuel can damage the fuel pump

Consistently driving your car on low fuel can cause a number of internal issues for your vehicle over time. Petrol in an empty fuel tank can collect debris that has built up over time and when this is pumped through your vehicle it can clog up various components such as your fuel pump and filter. A low tank can also lead to the vehicle pumping air, which may also cause issues for your fuel pump and other components that require fuel to function.

3. A completely empty fuel tank can be dangerous

The consequences of running out of fuel are a sudden loss of power to your engine, potentially on a busy road. This in itself is dangerous. Now consider having to pull over without the use of your engine if you are on a hill or in the middle lane with no hard shoulder it’s impossible. Being stranded in your car is always a potentially dangerous situation to be in and not one worth risking.

What to do if I have a completely empty fuel tank

If you have a completely empty fuel tank and your car cuts out whilst you are driving, you should put your hazard lights on and leave the vehicle only if it is safe to do so. If it is not safe to do, such as in the outer lanes of the motorway. Depending on the terrain and how busy the road is it may be possible to push your car to the side of the road. You should only do this if there are at least two people to help and you should always remain behind the wheel to control the car. NEVER PUSH A CAR ON YOUR OWN OR DURING BUSY TRAFFIC NO MATTER WHAT OTHER PEOPLE SUGGEST.

If you’re by the side of the road and you have run out of fuel then you should walk to the nearest petrol station if there is a pavement to walk on and it is safe to do so. Here you will be able to purchase a petrol can fill with fuel so that you can restart it again. If your car is completely empty, you may require two cans to start it again and this will only get you as far as the petrol station to refill properly. Ensure you lock the car and only leave it if it is parked in a legitimate position.

Nelson Xavier Ssenyange @NelsonSsenyange

Team Leader

Germax Auto Spares & Garage @GermaxASGarage


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