When fuel prices spike, which is almost a monthly occurrence in South Africa, lots of tips and tricks to save on fuel get bandied about, and the market gets flooded with a swarm of magnets and tablets and other “wonder” inventions. In this article we list a few tips that don’t violate the laws of physics, compromise your safety or insult your intelligence.
Regular Maintenance
Did you know that a vehicle can burn up to 30 per cent more fuel if proper maintenance is not performed on a regular schedule? We all know the importance of regular car maintenance, but for many reasons, we just don't do it often enough.
• Use the correct grade oil - You can improve your fuel mileage by 1 to 2% by using the manufacturer's recommended grade of motor oil. For example, using 10W-30 motor oil in an engine designed to use 5W-30 can will decrease your fuel consumption by 1-2%.
• Change the air filter - at least the set number of times outlined in the owners manual, more if you drive in dusty conditions.
• Corroded battery cables - cause the alternator to work harder, using more fuel. Have them cleaned as a matter of course with each engine check-up.
• Have a regular engine check -up. Since the advent of computer controlled fuel injection, there is no such thing as an old fashioned "tune-up" any more. At worst, you may be expected to replace spark plugs, oxygen sensor, the air and fuel filters.
• Don’t Neglect the Oxygen Sensor - If your car was built since the mid-1980s, chances are it has an oxygen sensor in its exhaust system. It should be replaced just as you would spark plugs, following the manufacturer's recommendations. This little device trims the fuel delivery and has a profound effect on fuel economy in the process.
• Inspect suspension - and chassis parts for misalignment. Bent wheels, axles, worn shocks, and broken springs can contribute to drivetrain drag, not to mention the unsafe condition they create.
Reduce the weight and Drag of your car
• Remove excess weight - Think carefully about what you need on a journey. If you do not need something, do not pack it. Removing excess wight from your car reduces fuel consumption. An extra 50 kg in the boot reduces a typical car's fuel economy by 1 to 2 per cent. Things like golf bags are typical offenders.
• Reduce Drag - remove roof racks if not needed, as they create wind drag. A typical roof mounted cargo box increases fuel consumption by up to 20%. Similarly, open windows and open sunroofs create extra drag, especially at high speeds. Over 50 Km/h, it is more efficient to run the vehicle’s aircon than open the windows to achieve ambient temperature.
• Avoid rough roads - whenever possible, because dirt or gravel can rob you of up to 30 per cent of your fuel mileage. Every time the wheels bounce up and down, forward motion energy is removed from the vehicle. The increase friction of the road surface causes the driver to apply more throttle - wasted fuel.
Tyres
• Check your tyre pressure - at least once a month. Under-inflated tyres burn more fuel. If tyres are underinflated, say 2 bar instead of 2.5 bar, the rolling resistance of the tyres increases by 5 per cent.
• Choose the correct tread - SUV owners should consider switching from an aggressive patterned off-road tread to a fuel efficient highway tread.
Alter your Driving Style
• Slow Down – According to the AA, dropping from 130km/h to 110km/h could save yo up to 25% in fuel. On smaller roads, slowing down from 110km/h to 95km/h could saver another 10%
• Drop the Revs - Some motorists let the revs (revolutions per minute or RPM) run to 3,000 per minute (petrol car) and 2,500 (diesel) before changing up a gear. It’s more efficient to move up a gear at 2,500 (petrol) and 2,000 (diesel). Use high gears, such as fifth and sixth gears, sooner than later. Driving at 60 km/h, a vehicle will use 25 per cent more fuel in third gear than it would in fifth
• Drive steadily - Harsh Braking and harsh acceleration wastes fuel, in addition to the wear of other components. Read the road ahead, anticipating the actions of other drivers and potential hazards. The less braking and accelerating, the less fuel consumed. For example, on a speedbump infested road, Braking hard, accelerating, then braking for the next speed bump is inefficient and uses extra fuel. Try to drive along at a steady 30km/h instead.
General Driving Habits
• Don’t Idle Unnecessarily - Don't let the vehicle idle for more than a minute. Idling consumes 3-4 litres per hour and pumps needless CO2 into the atmosphere. The modern, correctly tuned engine will consume less fuel turning off and re-starting than idling for extended periods.
• Watch the Onboard Computer - If you have an onboard trip computer, you probably have an "Instant fuel economy" setting. Watch this gauge and keep the litres per 100 kilometres as low as you can.
• Use Cruise Control - When appropriate, use your cruise control. This can save you up to 6 per cent in fuel consumption on the highway.
At the Service Station
• Fill Up More Often with less - While it may be somewhat inconvenient to fill up more often, carrying excess weight wastes fuel. If you vehicle has a 100L tank, that’s 75Kg worth of petrol. By always filling up to half full, you save significant kilograms.
• Choose the right octane fuel - for your car. Check the owner's manual to find out what octane your engine needs. Octane ratings measure fuel's ability to resist engine knock. But the higher the octane, the higher the price. Only about 4 per cent of cars in South Africa sold need premium fuel, mostly high performance turbocharged cars with a compression ratio below 10.5. Resist the urge to buy higher octane fuel for so-called "premium" performance – it offers absolutely zero performance or fuel consumption benefit on your average normally-aspirated vehicle.
• Take advantage of vouchers and cashback - at certain service stations. Most service stations have reward programs with either banks, insurance companies or retail companies which offer to encourage you to use their station.
Planning Ahead
• Combining errands - into one trip saves you time and money. Several short trips taken from a cold start can use twice as much fuel as a longer multipurpose trip covering the same distance when the engine is warm. Trip planning ensures that travelling is done when the engine is warmed-up and efficient.
• Drive less – carpooling, using public transport or the Gautrain, or even delivery food services, can all save you money! Obviously, you would need do the maths and see if it makes sense in your circumstances.
Summary
There is no miracle product which will suddenly decrease your fuel consumption overnight. The only real solution is to adjust your driving habits and drive sensibly; making sure that your car is serviced regularly; and reducing the weight and drag of your car where possible.
You can also keep your fuel system in peak condition by using injector cleaner, on promotion this week on Start My Car.
Work out how much fuel you use every week. Now try follow the steps above for a week and see what difference it makes.