You may have heard of Stop Start or Stop-Start systems and wondered what they do.
Stop-start system does exactly what its name says.
It stops the engine when the car comes to a halt and restarts it once you start accelerating.
In cars with automatic transmissions, the engine restarts the moment the driver lifts his or her foot off the brake pedal.
For cars with manual gearboxes, the engine is restarted the moment the driver “clutches in” or depresses the clutch pedal.
When regularly activated, a stop-start system can actually save you quite a bit of petrol.
Every day, many of us endure rush-hour traffic.
We sit in our cars with our cars idling, waiting for the lights to change or for cars to start moving again.
The stop-start system shuts off the engine and saves you fuel.
There are some downsides to stop-start systems, though.
Firstly, when the engine is switched off, it won’t be long before the cabin starts heating up.
Depending on the make and model, the system may keep the air-con running (on the car’s battery) for a while.
It could also switch off the air-con compressor but keep the fan blowing air into the cabin.
Either way, if you have to wait for a few minutes before traffic starts moving, the cabin may become uncomfortably warm.
However, the air-con or blower cannot keep going indefinitely.
The stop-start system will restart the engine to help maintain your climate settings.
Secondly, stop-start systems can be annoying.
In some models (typically smaller cars), the engine restart is accompanied by a very palpable shudder.
Thirdly, stop-start systems may accelerate battery wear since the engine has to be restarted multiple times in a single journey.
This is true even if you use batteries meant for these applications.
Lastly, although stop-start systems can save you fuel, it is hard for the average motorist to actually realise this.
To do so, you’d have to track (with the help of your car computer) your fuel consumption over a period of time with the system enabled.
You’d then have to compare this to the same period of time when the system was disabled.
Few drivers will remember to do this, or even want to spend time doing this.
Let’s not forget the numerous other road and driving conditions that affect fuel economy.