J1000
Rising Sun Member
It depends on the year of the vehicle but for most cars 1982 to 00s they run the IM240 rolling road test, look under the car for the cat, and check the gas cap seals. OBD has no impact on the pass/fail grade luckily.I think they still check for codes dont they in addition to the dyno run?
I believe newer cars can pass only by plugging in to OBD, but if it fails that they can pass by being clean on the IM240 test.
Apparently I can't pull up the Air Care Colorado site on my phone otherwise I'd link the page but if you Google Air Care Colorado IM240 you'll see the test info.