How does the system work, and does it really help you to save fuel?

There are two schools of thought when it comes to the Stop-Start technology. On one hand, there are those who like the idea of automatically saving fuel and rave about how it is so smooth and quiet that you almost don’t notice it. On the other hand, sceptics question its fuel-saving feature and dislike how it is too intrusive and abrupt, especially on Singapore’s urban roads.

So what is the Stop-Start system and how does it work?

How it works
As the name implies, the system kills the engine whenever the car comes to a halt, and restarts it again when you begin accelerating. The system works a little differently from make to make; in essence, when you brake to a halt, the system senses it and disengages the engine. Once you step on the clutch (for manual cars) or accelerator pedal, the system restarts the engine. This helps to save fuel while you wait for your turn to move.

Before this system was developed, your car would continuously sip away fuel while it is idling. This system thus saves you fuel every time you stopped. In Singapore’s constant stop-and-go urban road environment, this system offers many opportunities for saving fuel.

Disadvantages of stop-start technology
So how much fuel do we really save? That’s a tricky question to answer. However, you can easily track it with your car’s odometer. If your car has a Stop-Start deactivation button, drive with and without the system on to compare.

Despite its fuel-saving function, this system has its fair share of detractors. Some have raised concerns about the increased load on the car’s battery, which is needed to start the engine every time you stop-start. Others have pointed out that the air conditioner will also be turned off in stop mode. If the wait is long, even if the air conditioner fan keeps running, you may start to feel stuffy — especially here in hot and humid Singapore.

Although the response speed of the system has improved over time, the slight shudder that some feel when the system kicks in is still noticeable. And when it comes to parking, it’s probably a good idea to deactivate the Stop-Start function, if possible — you don’t want the distraction of the engine going on and off while negotiating a parking lot.