How do states use OBD II for emission inspections?

Many states connect a computer directly to a vehicle's OBD II system. The inspector can then read "faults." In some states, this type of inspection has replaced the tailpipe emission test.
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Working on your vehicle
Note the following before you begin working
on your vehicle: ...
Convertible Positives
It takes about 30 seconds to raise or lower the power-retractable hardtop. It
motors up and down smoothly and quietly, which isn't common, even among luxury
models. And in what was the most welcom ...
Minimum octane
Typical pump octane label
Volvo recommends premium fuel for best performance, but using 87 octane1 or above
will not affect engine reliability.
Volvo engines are designed to achieve rated horsep ...
