There are a lot of myths associated with cars in particular. Let’s bust a few of them for you.
Not using AC and rolling down the windows boosts fuel economy
Keeping the windows down and not using the AC maybe helpful in boosting the fuel economy at lower speeds, however as the speeds rise, keeping the windows down will reduce the fuel economy. Why? Because as the speeds increase, the wind forces increase as well. Keeping the windows cause more drag which will result in lesser fuel economy. If you really want to save fuel and not put on the AC, keep the windows up, keep the blower on in outside-circulation mode.
Over-inflation is more risky than under-inflation
People have a feeling that over inflating a tyre is riskier as it will cause a tyre burst. However, under inflating a tyre is more risky. While driving, if the tyre is under inflated, it will generate more heat due to more friction. Running on the highway or on long distance trips with lower tyre pressure will cause the tyres to heat up a lot and that may cause a tyre burst. Most cases of tyre burst happen due to under-inflation not over-inflation.
Premium fuels mean more performance
No, this is not true. Premium fuels will only benefit those engines that require it. Say you have a high end sports car or a turbo charged petrol vehicle (like a Polo GT or a Punto Abarth), only then will a premium fuel make some difference. In most normal everyday cars, it will not make any difference. One more thing, if you do want to opt for a premium fuel, opt for one that has a higher octane number (petrol) rather than one only having additives.
Engine warm up
People earlier believed that the engine needs to be warmed up before you could start driving the car. However, that is not true. What should be done is to drive slowly at low rpms till the engine heats up. Don’t revv the engine hard and don’t lug the engine either. Drive slowly and smoothly till the engine heats and you will be fine.