Drag or wind resistance is the main cause of high fuel consumption. Learn how to save fuel by driving behind a larger vehicle and using your vehicle’s inertia to move ahead without using fuel.

There is one good way to improve fuel efficiency and one dangerous method – the first is coasting and the other is slip-streaming. Let’s take a look at coasting first.


When you aren’t accelerating and the kinetic energy developed already by the car is taking you forward, it’s called coasting. Coasting dissipates energy to counter drag and rolling resistance by dropping speed in the process. It can be used smartly instead of braking at times. When you can see a red light from a distance or slow moving traffic in front of you, and you know that you will have to brake to stop as you near it, ease off the accelerator and let the car come to a halt by shedding speed on its own.

Avoiding unnecessary idling

What is idling? It’s the idle speed or RPM at which an engine runs without applying any gas. The engine is thus staying on by being fed fuel to do no work when the car is in neutral. Once you change gears to first and step on the accelerator, the engine speed increases and you get going.

We have grown up with the knowledge that idling your car for a few minutes on a cold winter morning is good for your car. It is not. In the good old days, it was fine as it prolonged the life of the engine but present day fuel injection systems have eliminated the need to idle your car. At idling speed, the engine doesn’t completely burn fuel leaving fuel residue on cylinder walls. This contaminates engine oil over time and will require sooner oil top-ups. Unnecessary idling also makes spark plugs dirtier and as a result fuel consumption increases.

Clutching it right

Every car has a clutch, whether a manual or an automatic. You don’t physically use one in an automatic but you can’t do away with it. That’s because a car’s engine runs all the time once you start a car but the wheels don’t. At times when they don’t, the two need to be disconnected from each other and here, the clutch coupled with the gearbox act as the disconnecting tool. It also helps in changing engine speeds as you upshift or downshift but that’s another topic altogether. Let’s focus on the clutch, its usage and its effects on fuel economy.