Automotive start-stop system - how does it affect fuel consumption and can it be turned off?

In the past, when the car suddenly stalled at idle, it was probably a precursor to a problem with the stepper motor. Now, a sudden stop of the engine at a traffic light does not shock anyone, because the start-stop system is responsible for this on board. Although it is primarily designed to reduce fuel consumption, it was not designed solely for this purpose. Do you need such a system in your car? How does it work and can it be turned off? To learn more!

Start-stop - a system that affects CO2 emissions

The system, which turns off the engine when stopped, was created with the environment in mind. Manufacturers have noticed that fuel in cars is wasted, especially in city traffic jams and waiting for traffic lights to change. At the same time, a lot of harmful gases are released into the atmosphere. So the start-stop system was invented, which temporarily turns off the ignition and immobilizes the power unit. This solution should help reduce the level of harmful compounds emitted into the atmosphere when the engine is not running.

How does start-stop work in a car?

The principle of operation of this system is not complicated. The whole process consists in turning off the ignition and immobilizing the drive. First, several conditions must be met. These include:

• complete stop of the vehicle;
• correct coolant temperature;
• turning off high-current receivers in the cabin;
• closing all car doors;
• sufficient battery power.

There is one more condition, perhaps the most important, regarding the gearbox. Let's move on to this issue.

Start-stop in manual and automatic modes

On vehicles with a manual transmission, the gear lever must be in the neutral position. In addition, the driver cannot press the clutch pedal because the system sensor is located just below it. The start-stop system is activated when you stop the car, shift into neutral and take your foot off the clutch.

In a car with an automatic, it's a little different, because there is no clutch pedal. Therefore, in addition to the actions listed above, you also need to press and hold the brake pedal. The function will then run. When you take your foot off the brake, the engine will start.

Start-stop function - can it be disabled?

Once you know what the start-stop system is, you might consider turning it off because you don't necessarily have to like it. After all, not everyone likes it when the car stalls every now and then in the city and has to be restarted. Some drivers feel more confident when they hear the car's engine running. It's hard to do anything about it. However, manufacturers have foreseen such a situation and placed a button to turn off the system. This is commonly referred to as "auto-stop" or simply "start-stop". Unfortunately, you usually have to activate it every time you get into your car.

Stop-start system and effect on combustion

Car companies often give different fuel consumption figures, mostly for marketing purposes. Nothing excites the imagination like numbers, right? It must be frankly admitted that the start-stop system reduces fuel consumption. However, these are often extreme values, depending mainly on the terrain on which you are moving. Most of all, you can save in a heavy traffic jam, and the least - with mixed driving in the city and on the highway. Tests show that the profit does not exceed 2 liters per 100 km. It's a lot?

How's that for fuel economy?

Values ​​measured per 100 kilometers can be a little misleading. Rarely does anyone travel such a distance in a traffic jam, right? Usually it is several hundred meters, and in extreme conditions - several kilometers. During such a trip, you can burn about 0,5 liters of fuel without a start-stop system and about 0,4 liters with an active system. The smaller the plug, the smaller the difference. Therefore, you should not count on special fuel economy with the system turned on. Environmental issues are more important here.

Start-stop system in the car and its equipment

What is the cost of using this feature in cars? In addition to the convenience of automatic shutdown and engine start, certain costs must be taken into account. which the? A larger and more efficient battery is required for proper and long-term operation of the system. The manufacturer must also use a more efficient and durable starter motor, as well as an alternator that can handle the capacity of the battery that stores electricity. Of course, you will not pay for these items when you buy them, but their possible failure can cost you dearly.

Which start-stop battery to choose?

Forget about standard and small lead-acid batteries, because they are not suitable for such a car. They use EFB or AGM models which have a much longer life span than traditional ones. They are also more spacious and durable. This is of course followed by a higher price, which sometimes starts from 400-50 euros. The start-stop system means high costs when replacing the battery, as well as when the starter or alternator fails.

Is it possible to permanently disable the start-stop function?

It is not possible to permanently disable this system from the cockpit (with the exception of some Fiat models). The button located on the dashboard or on the central tunnel allows you to temporarily disable the function. It will not work until the engine is manually turned off and restarted using the key or card. However, there are ways to completely disable this system without much intervention in the mechanics of the car.

How to get rid of the start-stop system in the car?

Usually the only effective way is to visit a specialized electromechanical workshop. Using the appropriate interface, the specialist intervenes in the operation of the on-board computer and changes the values ​​\uXNUMXb\uXNUMXbresponsible for starting the function. The start-stop system, like any other electrical system, has an excitation current. On some models, setting the limit above the nominal limit will cause the system to not start. Of course, the method does not work the same on all car models.

How much does it cost to permanently disable the start-stop function?

Car services that specialize in permanently disabling this system adjust the price of the service for a specific car. In some cases, only a slight voltage correction is sufficient (some cars of the VAG group), while in others more complex interventions are required. Therefore, the estimated cost in city cars and other light vehicles ranges from 400-60 euros, but it may happen that the specialist will have a difficult task, and you will have to reckon with a bill exceeding 100 euros.

Reducing the emission of harmful compounds during parking has been the goal of vehicle manufacturers. Thanks to the system, you can save on fuel. However, these will be microscopic profits, unless you move around a congested city very often. If the start-stop function annoys you, just turn it off when you get into the car. This is the cheapest way to deactivate.