We discuss the importance of battery maintenance, tell you why the cooling system needs coolant, and explain the possible causes of the dreaded “check engine” warning light.

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My dealer told me that I have a “maintenance-free” battery. Does this mean I don’t have to do anything to it?

Maintaining your car battery is something every driver has to do – unless you like getting stranded. Your car battery is responsible for providing the energy needed to turn your engine over.

After that, the alternator takes over the task of providing electricity to components such as the infotainment system and headlights. But if there’s not enough, the extra juice needed is drawn from the battery’s stored power.

The tropical climate is responsible for much of the wear and tear experienced by our cars. Together with humidity and age, battery terminals can get corroded. When this happens, the battery won’t be able to transfer its power. Clean the battery terminals regularly to help prevent corrosion.

If you don’t have a maintenance-free battery, you will need to top it up with distilled water from time to time. Check it every week and ensure that the water level doesn’t fall below the minimum line.

Lastly, your car battery is charged via your vehicle alternator, but this only happens when your engine is running. Most cars whose batteries are in good condition can withstand not being started for two weeks.

However, if your vehicle is constantly idle, there is a chance that your battery will eventually go flat. Get somebody to drive your car regularly. Even 30 minutes three times a week should be enough to maintain your battery’s charge. 


Do I have to put coolant in my car’s radiator? Isn’t water enough? I heard that these coolants are actually anti-freezes, which are not applicable to a hot and humid place like Singapore.

The coolant used in a car’s cooling system has the ability to raise the boiling point of water as well as lower the freezing point.

In fact, a 50 percent mixture of coolant – usually ethylene glycol-based – with water will raise boiling point to 108 deg C and lower freezing point to as low as minus 39 deg C.

The latter is, of course, not relevant to Singapore’s climate.

But having an appropriate amount of coolant in the car’s cooling system is necessary for a couple of other reasons (besides raising the boiling point by 8 degrees).

Radiator coolant contains a rust-inhibitor. This is crucial, since water can cause rust.

If you do not have enough coolant in the radiator, rust will form over time. And you can see this when the radiator water turns rusty orange.

In addition, the coolant has the property to provide lubrication to the water pump shaft, hence reducing wear. Having a coolant mixture instead of plain water in your car’s radiator is therefore important and necessary. 

My car’s “Check Engine” warning light flashes intermittently. It goes off when I switch off and restart the engine, but eventually re-appears.

Most times, it is triggered when I accelerate hard. My car is a six-year-old family saloon with a turbocharged 2-litre 4-cylinder engine.

This warning, dreaded by many, indicates a variety of faults – ranging from something as simple as a worn spark plug to more serious and expensive issues such as a damaged cylinder head.

Drivers have no way to pinpoint the defect. Only service centres with the necessary computers and software are able to find the exact source of the fault message.

If the light comes on when you are accelerating with full throttle, then it is highly likely that the engine is misfiring. “Check Engine” warnings resulting from misfire are common. They are not serious, but can lead to degradation of performance and economy in the long run.

Often, a misfire could be caused by worn spark plugs or one or more failing ignition coil-packs. Ignition coil packs are electrical devices which supply high voltage to the spark plugs.

Both these components have a lifespan.

Although it may be rare, a full throttle misfire in a turbocharged car could be caused by overboost. This happens if you somehow manage to increase the boost pressure or if the electronic boost controller malfunctions.

Either of these should be rectified immediately. Unintended overboost is extremely detrimental to the engine.

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The Check Engine light indicates a serious fault with the vehicle.