I'm sure Texas isn't much different from any other state.
We want clean air. So, the auto manufacturers came up with a glorified box of charcoal that "filters" out the pollutants (simultaneously making the energy output less efficient requiring yet more fuel) called a Catalytic Converter.
Most cars' converter lasts about 10 years.
I'm driving a Honda Accord from 1998. The coverter has given up the ghost and I don't pass the Nox tests.
So...
I can't renew my Registration and have to spend about $1700 to replace that stupid box of charcoal.
That is...unless somebody can suggest a way to pass (legal, of course) without paying that kind of cash.
Anybody have any ideas???