contents
- The start-stop automatic: A technology with controversy
- How does a start-stop system work?
- Is a start-stop system harmful to the engine?
- When does the start-stop system switch?
- How can I tell if a car has an automatic start-stop system?
- Automatic start-stop does not work – what to do
- Who invented the start-stop system?
- Conclusion
The start-stop automatic: A technology with controversy
As the Start-stop automatic was installed on the first models, there was a lot of controversy. The introduction of this technology is still controversial – among drivers and experts alike. The subject of this discussion is a whole series of open questions that have not yet been definitively answered, either scientifically or technically.
Does shutting off the engine when idling save enough fuel to make start-stop worthwhile? Doesn’t switching it back on use more fuel? Above all, however, the question arises whether the frequent switching on and off – especially when there is heavy traffic – damages the engine itself and other components or not? We get to the bottom of these questions and provide you with clues that you can use to decide whether an automatic start-stop system makes sense for you or not.
How does a start-stop system work?
the automatic start-stop technology has the function of switching off the engine when the vehicle comes to a standstill and is idle for more than a few seconds. As soon as the driver presses the accelerator pedal or releases the brake, the engine switches on again – so it’s really quite simple in principle.
Proponents claim that this technology can save between 3 and 5% fuel in stop-and-go traffic. In city traffic, a total of up to 15% fuel savings should be possible – in the best case.
The start-stop system in hybrid vehicles
The constant further development of hybrid and electric vehicles has contributed enormously to the development of start-stop technology because: Especially in hybrid vehicles, most models are equipped with the start-stop system. However, this almost always works a little differently here than is the case with cars with combustion engines. The on-board computer monitors RPM, throttle and speed. In this way, the system can determine when the car is coasting to stop at traffic lights, for example. If this is the case, the petrol engine is usually switched off at a speed of around 15 km/h. The electric drive is sufficient for the last few meters.
Also will the energy generated during deceleration is recuperated, i.e. stored in the battery. With these models, a little pressure on the gas pedal is usually enough to restart the combustion engine. It is amazing that the technology completes this process in a few milliseconds, much faster than the blink of an eye takes.
Is an automatic start-stop system harmful to the engine?
It’s true that that Starting the engine has the greatest effect on the engine itself and that is where the greatest wear and tear occurs occurs. If an engine has not been in operation for several hours or days, a so-called cold start takes place. The wear is caused by the high temperatures when the air-fuel mixture ignites and the components of the unit that are still cold, which suddenly expand. In particular, the bearings and the cylinder head gasket are extremely stressed during this procedure. However, wear and tear decreases exponentially when the engine is warm.
This is the reason why some drivers have an auxiliary heater with engine preheating installed, because this technology ensures that the unit does its job for a very long time. And it’s the reason why always is advised to drive a cold engine very gently during the first kilometers and not immediately demand maximum performance from him.
Two parts of the car that are loaded when the engine is started and thus also by a start-stop system are the starter and the battery. In order to counteract this constant stress, manufacturers are now using reinforced components that can cope with these requirements.
The actual load when starting the engine with the start-stop system
the The automatic start-stop system has to be seen in a special context because it only comes into play when the car is already running and in traffic. Accordingly, it is not harmful to the engine, because it is no longer completely cold. It was only active a few seconds ago and it’s still hot. In addition, the automatic start-stop system restarts a stationary car if the engine temperature drops significantly, provided the key is in the ignition lock.
Modern drive units are designed in such a way that they can usually withstand 100,000 start cycles. Applied to the average life expectancy of a car, which is 12 years, this means 22 cold engine starts daily.
Even with the start-stop system, there is no need for manufacturers to design engine mounts that can withstand 250,000 or more start cycles. The wear on the engine is many times lower than with a cold start. In addition, engines are now extremely robust. For this reason Drivers don’t need to worry about the minimal extra wear when restarting.
When does the start-stop system switch?
When the start-stop system switches the engine on and off depends on how the system was designed. Switching off usually occurs when:
- the vehicle has come to a standstill and the brake is applied.
- or / and the neutral has been engaged.
- or when the clutch is depressed.
- the system detects that the car is coasting, as is often the case with hybrid vehicles.
- the internal combustion engine is not needed. This can be the case with a hybrid vehicle if the power of the electric motor is sufficient on a downhill road.
To start the combustion engine, depending on the model and the type of system, it is necessary:
- take your foot off the brake pedal.
- and/or put it into gear.
- and/or stepping on the clutch.
- and/or press the gas pedal.
How can I tell if a car has an automatic start-stop system?
The easiest way to determine this is to look at the dashboard. You can find that here Start-stop automatic symbol, the car is also equipped with it. The symbol is an A surrounded by an open-bottomed circle with an arrowhead at the right end. If this symbol lights up green, the automatic start-stop system is active. If the symbol lights up orange or red, there is a fault.
A is also helpful Look at the operating instructions, where it is explained exactly how the automatic start-stop system is deactivated and then activated again. How a driver can completely switch off the automatic start-stop system is not explained, as this is generally not possible.
Start stop automatic does not work – what to do?
The most common cause of a malfunction or failure of the automatic start-stop system is the vehicle electrical system voltage. Is the Operating voltage too low, the system automatically switches off the automatic system. This would otherwise not be able to restart the engine due to a lack of electrical energy. Reasons for a drop in voltage can be:
- Battery defective.
- Charge controller defective.
- too many consumers switched on. In particular, if consumers such as additional headlights, a sound system or a cool box have been installed later, the on-board voltage can drop. Especially when the air conditioning, lights and other consumers such as infotainment or the charging station for the cell phone are activated at the same time.
- Error in the wiring.
- System error in the programming of the automatic start-stop system.
In some vehicles, the automatic start-stop system is sporadically active, but then fails again. This is a good indication of either too many consumers or a battery that is declining in capacity.
In cars with a healthy battery but with an auxiliary heater, it can also happen that the automatic start-stop system remains deactivated for the first few kilometers until the battery has been recharged. However, this only happens if the auxiliary heating was switched on beforehand.
Who invented the start-stop system?
The start-stop system is a technology that their Beginnings in the 1970s would have. The first car with this automatic was the Toyota Crown. However, it was also the last model for the time being, because the system was not able to establish itself at the time. Around 10 years later, Audi and VW revived this technology and introduced it to several models. With these, the engine could be switched off by pressing a button. The unit started up again automatically as soon as the gas pedal was pressed.
Conclusion
The start-stop system is part of the constantly growing group of assistance systems that make driving more comfortable and safer in modern vehicles. In addition, this technology brings fuel savings, which can be up to 15% in the best case. However, not all systems work equally well. Therefore, car buyers should definitely take a test drive. Stepping hard on the brakes without stopping shows whether the technology in the respective model is mature or, in case of doubt, is rather a hindrance.
Customers can currently still opt for cars in which this technology is not part of the standard equipment. However, it is foreseeable that the automatic start-stop system will have had its day at the latest with the complete switch to fully electric cars. Electric cars do not need this technology, which is one more reason to opt for such a model today.
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