Don't let it idle –Drive off immediately after starting the car in the morning. Do not let it idle for any length of time, especially when the engine is below normal operating temperature. This will reduce the amount of time the engine has to inhale the over-rich fuel mixture required for starting and idling. Such a mixture is wasteful and contaminates the oil to such an extent that prolonged idling can ruin an engine. Go slow at first, to allow the engine, gearbox and final drive to warm up.
Go with the flow –Drive at a reasonable pace in town. Stay with the traffic, because if you slow down too much you will not only be an obstruction but you may also have to change down to a lower gear. A lower gear usually, but not always, means your vehicle will use more fuel.
Gentle on the throttle –Accelerate slowly and use the lower gears when you start from a speed below 1500 r/min to avoid over-stressing the engine. Large throttle openings will obviously increase the fuel flow rate.
Drive (slightly) slower –Reduce your habitual cruising speed by 10 km/h. This will result in a measurable drop in fuel consumption because the air resistance increases dramatically with an increase in speed.
Anticipate the traffic – Try tobrake as little as possible. Braking converts the car’s momentum into heat energy. When you accelerate again the engine has to supply the lost energy to get the vehicle back up to speed again.
Avoid roof racks and trailers –Carry excess luggage inside the car as much as possible. A roof rack or a trailer increases the air resistance dramatically but an increase in weight only increases the amount of fuel being used by a significant amount while you accelerate, not while you’re cruising.
Check your tyre pressures every two weeks –Soft tyres not only have a negative effect on fuel consumption but are also a major cause of blowouts.
Look after your car –Have your car serviced regularly to ensure it is in optimal working condition.
Keep score –A record of fuel consumption using the tank-full to tank-full method is a good way to remind yourself about saving fuel. This system works fairly well if you do not let the pump attendant trickle fuel in after the automatic pump was activated. Investigate any unreasonable change in fuel consumption.
Windows shut –Driving with open windows or activating the air-con will increase your fuel consumption by a few per cent but you must be fanatic about reducing consumption to drive like that.
Also have a look at this video which explains the concept of "hypermiling".
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