Thank You vt_Maverick ..,now I already drive 994 miles and I think I will adds 600 miles before go to other inspection ,because each time fails I had 30 days for fixing the problem if fails again I think I will buy the use OBD but the question is when the scaner say the ODB cannot find any error code ,Is that means the ODB is ready to inspection or need to find other kind scaner for the state inspection test?