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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Engines
The Volvo XC90 is available with a choice of two high-performance engines -
one diesel and one petrol - both of which produce plenty of power and torque
from low engine speeds and through the mid- ...
Limitations
NOTE
• The sound source (AM, FM1, Disc,
etc.) being played through the infotainment
system's speakers cannot be controlled
from the rear control panel.
• In order to select and play an externa ...
Sport
In this mode, the vehicle's body sway is
reduced during cornering and steering
response is more immediate. The transmission
shifts up at higher rpm for sportier driving. The
indicator light in ...
