In the mid-90s I lived in the Dallas TX area and had just bought a 1971 Pontiac Ventura II. At that time and in that place, sniff testing was being tried out. It was the law but the program was a "trial". My car did not pass. Not enough of the exhaust was making it to the tailpipe, they said. During the grace period for repair, the emissions inspection program was cancelled. Dodged that bullet! The law returned to normal inspections like I had always seen in prior days regardless of state. A few years later I moved to Arkansas and had the same inspections as always n TX and LA. Then soon after that, even those inspections were discontinued here. My understanding is that when they did away with state inspection, laws were changed to allow traffic stops to check for those violations. Thats the extent of my emissions / inspection worries... currently there are none. Taxes are sky high though, and we mostly drive junk.