SOME weeks ago the Car Sewa coloumn mentioned that if the engine cranks slowly while starting the car early in the morning, it means the battery is low, and you need to push-start or jump-start the car.

A lot of people ask, "What do you mean by jump-starting a car?" A very good question.

In the days goneby, it was a common practice to start a car by pushing it. This is not recommended in cars with MPFI engines. All these engines have computer-controlled functions for various components. When you switch on the ignition, you activate the computer which in turn ‘alerts’ the engine. This is why you must switch on the ignition and wait for a few seconds before turning the starter. Some cars have an audio warning, ding, ding, ding. When the dinging sound stops, start the car. Some cars show a red light ‘no start’. It then turns green and flashes ‘start’. For all this to happen, the battery supplies the power. If the battery is ‘down’, the computer may not function. This simply means the engine is not ready to fire up.

At this stage if you push-start the car, you are not giving an opportunity to the computer to function. You could also damage some of the electronics in the car. Just as your computer has a shut-down procedure. The car, computer controlled, has a start-up procedure.

If your car is fitted with a catalytic converter, there is a very good chance that you could also damage the exhaust system.

Just keep in mind that the new breed of cars is not meant to be push-started.

If the battery is low, the only way to start the car is by ‘jumping’. This simply means making use of another car’s batteries. For this you need ‘jump wires’. This is a set of wires with which you will connect your low or dead battery to the car which has a full charge in the battery. Connect the battery as shown in the photograph, negative to negative, positive to positive. Rev up the engine of the car whose battery is in full charge. Give it a couple of minutes and the dead battery will be charged to some extent. In any case the batteries have been connected in series i.e. positive to positive pole and negative to negative. This means that even though one car battery is dead, it is working off the battery in the second car.

The car with dead battery can now be safely started. As you switch on the ignition, the computer has the power to carry out the pre-start function. Wait a moment, turn the key and the car will spring to life.

Let the car idle for a few minutes. One great advantage with the new breed of cars is that they have tachometers. That is the proper nomenclature for an r.p.m. meter. Idle speed is usually about 850 r.p.m. Once the car has warmed up i.e. the engine oil is in full circulation, rev up the engine to about 1200 to 1500 r.p.m. This will then charge up the dead battery in four or five minutes, enough to start the car on its own.

It is also time to disconnect the jump wires. This should be done carefully, the clamps should not touch each other, otherwise there could be sparking. Computers and other electronics in your car do not like sparks flying around. Who does? In a petrol engine car, sparks are not welcome. Other than the possibility of igniting petrol vapour, they will short circuit the electronic gadgetry in your car — like the diodes in the alternator. This can be easily avoided by being careful.

One word of caution. If your car battery is dead, it could be because of extreme low temperatures. Low temperatures also mean thick engine oil, which in turn means slow and sluggish circulation of engine oil. Do not rev up the engine as soon as the engine fires up. Ninety per cent of the wear and tear of your engine takes place in the first 90 seconds of the start-up. One way to destroy your engine is to rev up a cold engine. Only you can avoid this. Be gentle and kind to your car.

Happy motoring!