Why spend more at the petrol pump when you can easily spend less? The team at The Family Handyman shares this list of DIY tricks for a noticeable difference in your fuel costs.
Keep Your Tyres at the Right Pressure
Surveys show that 60 per cent of the vehicles on the road have tyres that are underinflated by at least 30 per cent. That's at least 9psi below the manufacturer's recommended pressure. That can cost you almost 7 per cent in wasted petrol. Plus, low air pressure causes premature tyre wear, and that can cost hundreds of dollars over the life of the tyres. For best results, check the air pressure in your tyres with a digital pressure gauge (about $20 at any auto parts store) and fill to the recommended pressure shown on the decal inside the driver's door or on the driver's door pillar.
Change Spark Plugs Before They Are Due
If your 100,000km spark plugs have 80,000km on them, they're 80 per cent worn. Misfires and incomplete combustion occur more frequently during that last 30,000km, costing you hundreds in wasted fuel. You have to replace your spark plugs anyway, so do it early and pocket the savings. Even if you have to replace the plugs one extra time over the life of your car, you will still come out way ahead. And don't automatically assume your plugs are good for 100,000km. Many four-cylinder engines require new spark plugs at either 50,000km or 80,000km intervals.
Change Your Air Filter Early and Often
Your engine sucks in over five million litres of air through the filter every year. On older vehicles (pre-1999) a dirty air filter increases fuel usage by almost 10 per cent. On newer vehicles, the computer is smart enough to detect the lower airflow, and it cuts back on fuel. So your engine will lack power and pick-up. Check the filter when you change your oil and replace it at least once a year, or more if you drive in dirty, dusty conditions.
Keep Your Car Aligned
If your tyres are bowed out of alignment by just 4mm, it's the equivalent of dragging your tyre sideways for 160km for every 30,000km you drive. That will cost you a few hundred dollars a year in wasted petrol, and it will wear your tyres out faster.
Here's an easy way to check your alignment without taking your car in to the mechanic. Buy a tread depth gauge and measure the tread depth on both edges of each tyre (rear tyres too). If one side of the tyre is worn more than the other, your car needs to be aligned.
Lead Foot = Lead Wallet
Hard acceleration in stop-and-go driving costs you 20 per cent more. If you live your life in rush-hour traffic and like to put the pedal to the metal, spend all your extra time at the next stoplight figuring out how you could have spent the extra cash.
Replace A Broken Or Missing Spoiler
The plastic air dam (aka "spoiler") that's broken or missing wasn't just for a sporty look. If your car had an air dam, driving without it or with a damaged one can reduce your fuel mileage. The air dam literally "dams off" airflow to the undercarriage of your car, forcing the air up and over the hood. That helps your car cut through the air with less drag. It also increases airflow to the A/C condenser and radiator, reducing the load on your car's electrical system.
How Speed Kills Your Wallet
Yes, you've heard it before, but how about some real-world numbers to drive the point home? Aerodynamic drag is a minor concern in city driving, but it really kills your mileage at speeds over 90km/h. In fact, increasing your speed to 100km/h increases drag by 36 per cent! If you do a lot of highway driving, getting to your destination a few minutes early could cost you several hundreds dollars a year. Keep it closer to 80km/h and use your cruise control. It will pay off.
Replace Your Oxygen Sensor Before the Light Goes On
Oxygen sensors monitor the efficiency of combustion by tracking the amount of oxygen remaining in the exhaust. But they degrade over time, and that can cost you up to 15 per cent in mileage. When they fail, the computer lights up your "service engine soon" light, forcing you to incur a diagnostic fee. On pre-1996 vehicles, replace your oxygen sensor every 100,000km to keep your mileage at its peak. On 1996 and newer vehicles, replace the sensors every 160,000km. Some vehicles have as many as four, but the sensors installed behind the catalytic converter rarely fail.
Save Money on Gas: Tips for Better Gas Mileage & Fuel Economy [The Family Handyman]
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