Update for car owners (if you have GTO plates)

[roberb7]

If you've been getting the biannual emissions test done at the testing station behind Encino, it's closed.
They've opened up a new one in Yerbabuena. It's just north of the Transito, on the same side of the road. So, to get there, you have to go past the Transito and Chevy dealership, make a U-turn, pass the Transito again, and there will be a large sign for the "Centro de Verificación" telling you to turn right and go up the hill.

[doncoulter]

Thanks for the tip, Bob. There's a list of all the local Centros de Verificación here. If you click on an address, a map opens in a new tab.

The last time my car was due for its checkup, I took it to the Nissan dealership. It has the advantage of being located next to the newest branch of Café Tal.