When a vehicle's emissions computer is reset, necessary emissions
information known as "Readiness Flags" are erased from the engine computer
memory. These flags are required in order to show the smog machine that the
required emissions components are present and working properly. Only after
this internal "Readiness" test is conduct can a vehicle pass a smog
inspection. Depending on how much driving you do, in order for a vehicle's
Engine Control Unit to set all the necessary "Readiness Flags", a vehicle
must be driven 1 to 2 weeks in order for the proper readiness flags to set.
Since your friend recently reset the trouble codes you have to drive your
vehicle for at least one week before taking or re-taking a smog test.
I hope this information is helpful to you. If there is anything I can help
with in the future, don't hesitate to e-mail.
posted by SmogTips Support 04-16-2010 10:11 AM