You’ve heard of Moore’s Law? Applied to computers, it states that processing power doubles – roughly – every two years.
A similar law – not yet named – arguably applies to new cars. Well, to the technology being fitted to new cars. Pressure – from consumers and Washington – to change things up is pretty intense. Cars, after all, have been around for a century and then some; the IC engine is old news. How do you make a new car “new”?
* Direct injection -
Over the past 30 years, car engines have gone from having fuel sucked into them (via carburetors) to having it sprayed into them (via fuel injection). The latest update is direct injection (DI) which is also a form of fuel injection, but with this big difference: The fuel is sprayed under extremely high pressure (thousands of PSI vs. the 30-40 psi used in conventional fuel injection) directly into the engine’s cylinders. Older fuel injection systems shot the fuel into an intake manifold (throttle body or TBI injection) where it was mixed with air before being sucked into the cylinders – or the fuel was sprayed into the airstream just ahead of the cylinders. But in neither case was the fuel sprayed directly into the combustion chamber itself. Why do this? It allows for even more precise metering of fuel – and that means less wastage, which means improved fuel mileage.
New car engines fitted with DI systems make a distinctive – almost diesel – slight rattling noise at idle. This is normal – don’t sweat it. And – usually – the noise is only noticeable when the hood is raised and you’re outside the car.
* Auto Stop -
Hybrids cut down fuel consumption by cutting off the gas-burning engine whenever it’s feasible to do so. Conventional cars are adopting the same strategy. When you roll up to a red light or are stuck idling in traffic, the car’s computer registers this stationary state and – automatically – cuts off the engine. When the driver takes his foot off the brake pedal – or pushes the accelerator pedal down – the computer automatically re-starts the engine (this happens almost instantaneously, using a very high torque electric starter motor) and off you go.
The fuel savings aren’t huge – but they are significant. Even half a mile per gallon matters – if not so much to the car’s owner as to the car’s manufacturer. All car companies are under tremendous pressure to improve the overall fuel economy of their new car fleets – and this is one of the ways they do it.
The first time your new car’s engine automatically stops may startle you – and ignite feelings of dread you’ve just bought a lemon. But don’t worry – it’s supposed to do this. And you can (usually) turn off the feature if you don’t like it.