It seems they have regressed slowly over the decades.
For over a decade now, all I've ever seen them do is drive the vehicle around the block, pull in to the garage and turn the lights on, watch in the wall mounted mirrors to see if the rear lights worked and blew the horn one time. I do remember one time a couple years ago, one inspection place pressure tested my gas cap. (no emissions testing here in my county)
20 years ago, out in San Angelo, they would look under the hood at the engine to see if the hoses for the emissions were still there and stick a mirror underneath to see if the catalytic converter was still there. If you had a check engine light on, they wouldn't pass it since check engine on most cars at the time was solely emission problems related.
30 years ago in Pensacola Fla and in Memphis Tn, they drove over a set of pads in the inspection bay and threw on the brakes to check how well each wheel stopped, did the headlight alignment check, checked each tire for wear, and looked the exhaust system over for leaks. The smallest ding or crack in the windshield failed ya, didn't matter if it was in the driver's field of vision or not.
It's odd about the revenue thing. When Tx went to no paper sticker a couple years ago, the cost at the inspection stations went down, but on the registration renewal receipt, I see there is a new charge now that says something about inspection. Instead of paying the full price at the inspection station, he now gets a smaller amount and the county registration office collects what amounts to whatever the govt would have lost.
