When you reset the computer, there are certain mappings that are relearned after driving. I belive it may be around 75 miles.
Many areas during emissions testing plug into the OBDII port. I have read posts on several forums where people were turned away and told to come back in 100 miles. The computer reads that it had been reset by a flag or how many miles since reset. Im not shure what it indicates by they can tell.
99 Durango 5.9, FT 4x4, IP stage III w/ K&N air hat, M1, SCT, Fastman TB, 1.7 RR, JBA headers, Borla cat back, Martin Saine valve body, Hotchkis swaybars, Blistein shocks, lowered 2" Black Rhino Kenya wheels, 246. 7 RWHP, 319 TQ