Many drivers experience start-stop system problems. They often dislike how it functions and deactivate it right after starting the car. However, some drivers want this system to save as much fuel as possible. Yet, they face another issue: the engine does not shut off as often as they expect. These start-stop system problems can be frustrating, leading to questions like, “If I bought a car with this start-stop system, why was it more expensive initially? Why does it use a costly battery? Will the fuel savings cover that difference?”
This article explains why the start-stop system won’t turn off the engine under certain conditions, highlighting common start-stop system problems.
Reasons the Start-Stop System Won’t Turn Off the Engine
The operation of the start-stop system depends on many factors. It receives information from various sensors and systems. For example, it monitors the transmission, speed, engine RPM, cabin temperature, and outside temperature.
It also gathers data from sensors that monitor the battery. Based on this information, the computer decides when to turn off the engine, which can lead to start-stop system problems.
Factors Influencing Engine Shutdown in Start-Stop Systems
- Engine Temperature and Performance: The system will not turn off if the engine has not reached operating temperature. It also remains active if the engine is overheating, such as in traffic jams.
- Power Consumers Affecting Battery Life: If too many devices are running in the car, the system may keep the engine on. This prevents overloading the battery and allows it to provide enough power.
- Weather Conditions Impacting System Activation: Extreme cold or heat can also deactivate the start-stop system.
For more insights into how the start-stop system can impact both the engine and battery, check out this detailed article.
Additional Reasons for Start-Stop System Deactivation
Other reasons include:
- a) The seatbelt is unfastened.
- b) The preset cabin temperature hasn’t been reached.
- c) The hood is open.
- d) The doors are open.
- e) The car is on a steep incline or decline.
- f) The parking assist system is activated.
Timing for engine shutdown varies among different cars and versions. Some systems can turn off the engine before the car completely stops, like at a red light.
Delayed Engine Start: Why Your Start-Stop System May Fail
Unfortunately, the engine will not always start quickly enough. This can create frustrating situations. For example, it may shut off just before the driver presses the gas pedal to move forward.
Variations exist between automatic and manual transmissions, but the concept is similar.
Automatic vs. Manual Transmissions: How They Affect Start-Stop Systems
In vehicles with manual transmissions, the engine starts when you press the clutch to shift gears. For automatics, the engine starts when you lift your foot off the brake or touch the gas pedal.
Why Does the Engine Start Even When the Car Is Stationary?
Sometimes the engine starts even when the car is stopped. This can vary based on the vehicle and the driver’s actions:
- a) You moved the steering wheel (even a slight movement can trigger a start).
- b) The cabin temperature changed, requiring heating or cooling.
- c) The battery has drained and needs to start charging (especially with multiple devices running).
- d) You lifted your foot off the brake (this can automatically start the engine).
- e) If on a slight decline, lifting your foot off the brake may cause the car to roll forward, prompting the engine to start.
Understanding Your Start-Stop System: The Importance of the User Manual
Not every start-stop system operates the same way. Driver experiences can differ significantly.
Battery life can also be an issue. A battery nearing the end of its life does not have a straightforward lifespan in terms of kilometers or time. Various driving conditions also affect performance.
If you already own a car with this system or plan to buy one, read the user manual carefully. Understanding how the start-stop system works will help set your expectations. This knowledge will prevent disappointment and unnecessary frustration, especially regarding start-stop system problems.