General Discussion
In reply to the discussion: Anyone else hate the auto-stop feature of newer cars? [View all]hunter
(40,896 posts)Before 2000 smog check places actually checked the integrity of emission systems and would stick a sensor into the car's exhaust pipe while it was running.
Now it's all done by computers. The smog check computer asks your car's computer if its emission control systems are all running within specs. If your car's computer says they're not your car doesn't pass. If the smog test technician sees anything sketchy under the hood your car doesn't pass.
Granted, there are a lot of technicians who, like Sergeant Schultz, see nothing, but it would take some sophisticated hacking to make a modern car's computer deceive the smog test computer.
I've only driven cars with the engine stop feature a few times and never in situations where it annoyed me.
The truck I drive is old, so old it requires an old-style smog test. There are only two places left in our city that can do those, all the other smog places have dumped the equipment required to test cars that are more than twenty years old.
I've driven hybrids and sometimes noticed a little hesitation as the gasoline engine is switched in and out but never enough to be alarming. Non-hybrids do that too, especially when an automatic transmission is switching gears.