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Start-stop system in cars

start-stop-engine سیستم استارت و استاپ اتوماتیک

Start/stop technology came to Europe first, due to regulatory differences. 25 percent of the New European Driving Cycle (NEDC) is spent idling.

In automobiles, a start-stop system or stop-start system automatically shuts down and restarts the internal combustion engine to reduce the amount of time the engine spends idling, thereby reducing fuel consumption and emissions. This is most advantageous for vehicles which spend significant amounts of time waiting at traffic lights or frequently come to a stop in traffic jams. Start-stop technology may become more common with more stringent government fuel economy and emissions regulations. This feature is present in hybrid electric vehicles, but has also appeared in vehicles which lack a hybrid electric powertrain. For non-electric vehicles fuel economy gains from this technology are typically in the range of 3-10 percent, potentially as high as 12 percent. In the United States, idling wastes approximately 3.9 billion gallons of gasoline per year.

Start/stop technology came to Europe first, due to regulatory differences. 25 percent of the New European Driving Cycle (NEDC) is spent idling. In comparison, only an estimated 11 percent of the United States United States Environmental Protection Agency (EPA) test is spent at idle. Start/stop activation depends on specific driver inputs as well as operating conditions. The engine must have reached proper temperature to get adequate light-off of its catalytic converter and also to ensure proper lubrication and as effortless a restart as possible. With a manual-gearbox car, engine shutdown typically comes with braking to a complete stop, gearbox in neutral and clutch release. Cars with automatic transmissions shut down upon braking to a full stop – the shut down is activated by the footbrake pedal being in use when the car comes to a halt. If the car is slowed initially by manual use of the automatic gear box and final stoppage is by use of the handbrake the engine will not shut down.

How does Start-stop system work?

The frequent cycling can strain internal engine parts, too. Most engine wear and tear happens during startup, so engineers have designed bearings that better self-lubricate and are slicker than normal bearings. Better self-lubrication means the engine will be better protected until pressurized oil arrives after the engine is running. Even without special bearings, engine oil technology has also improved, meaning there’s a better layer of protection already on the bearings to prevent excessive wear. With automatic stop/start and an automatic transmission, holding the brake after coming to a complete stop will usually trigger the system to shut down the engine. Lifting your foot off the brake (and, on some systems, turning the steering wheel) will restart the engine, usually bringing it up to speed by the time your foot reaches the accelerator pedal. With a manual transmission, shifting to neutral and releasing the clutch generally switches off the engine; pushing in the clutch pedal starts it back up, and the car is ready to go by the time you have it in gear. Depending on the vehicle, the engine may also restart if the climate control system needs additional heating or cooling; the system may also deactivate if the weather outside is above or below a certain temperature. Will this save you thousands of dollars in gas? Not likely, but if you live in a congested area, the few extra miles you might get from a tank of fuel will add up, as will the less-visible emissions benefits. More importantly, you shouldn’t have to worry about added stress on your car — it’s been engineered to deal with the new technology.