In urban situations especially, stop-start should be making a real-world difference, but will the durability of engines be affected in the long term?
What is stop-start technology?
Stop-start is a system on most modern cars that cuts the engine when the car is stationary in order to reduce fuel consumption and emissions. In hybrid cars, the same system may also shut down the combustion engine when the car is cruising at low throttle loads, when descending gradients and when decelerating from higher speeds. The engine starts again when the clutch is engaged or the brake is released, or when the driver is ready to move or accelerate again.
How does stop-start work?
The system uses a computer to detect when the car is stationary or out of gear, or when it's running in low-load conditions; at which point it halts fuel delivery and spark to the engine. In the case of hybrid cars, a limited amount of torque can be supplied by the car's electric drive motor while the engine is off, although it's usually only enough to maintain speed on a level grade or around town. The ignition starts again when the car begins moving, the clutch is pressed or more power is needed.
The process happens automatically, but drivers can choose whether the system is active or disabled by pushing their car’s stop-start button; a capital A with an arrow circling clockwise.
A conventional electric starter motor works by engaging a small pinion gear with a large ‘ring’ gear fitted around the outside of the engine flywheel.
The latest stop-start technology looks much the same but the motors are more powerful, faster acting and more robust, and often they're necessarily backed by higher-voltage electrical systems with bigger storage batteries. Some are designated ‘TS’ for ‘tandem solenoid’ and designed to cope more smoothly with scenarios where the engine is about to stop and then the driver accelerates again.
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Update the story please!
Don't Panic!
Positive crankcase ventilation (PCV)
Exhaust gas recirculation (EGR)
Vacuum amplifiers
Electronic ignition
Lead-free gas
Oxidizing catalytic converters
Air injection systems
Electronic Engine Controls
Fuel injection
Reducing catalytic converters
Sealed fuel tanks
Vapor recovery systems
Vapor recovery fuelers
Cam and crank timing sensors
Knock sensors
Mass airflow sensors
Manifold Absolute Air Pressure Sensors
Free oxygen sensors
Electronic throttle control
Variable valve timing
Low sulfur fuels
Diesel particulate traps
Hybrid ICE/battery electric vehicles
Multi-speed transmissions
Continuously variable transmissions
Multi-clutch transmissions
Urea injection and selective reduction catalysts
Direct fuel injection
Turbocharging
Intercoolers
...and most recently:
48V mild hybrids with start/gen units
LiIon batteries plus electric turbochargers
Continuously variable compression ratio crankshafts
...and, soon, camless valve systems?
With every add-on, stories like this one surfaced. But today's cars are more reliable than ever.
I should add that that long list of add-ons suggests we are nearing a tipping point for internal combustion engines. The work to create today's ICE cars has been fantastic....yet all are far more polluting than a simple electric vehicle.
Fasteddie
I worked it out once and it'll take over 7 years to pay for itself, and that's if the battery doesn't fail, have you seen the extra cost of stop start batteries! let alone the cost of a stop start starter motor.
The first thing me or the wife does after starting the car is turn it off! Apparently BMW's can be reprogrammed to do this by default, true BMW owners????
TL;DR: The engineers have