Emmissions Hell

Help!! I just bought a 93 Grand Am SE V6 3.3L. K...the guy swore to me that it would pass inspection cuz it had a new cat on it WHATEVER!!!!!!!! The nox is high about 10 points. The only suggestion I've gotten so far is to clean/replace the egr. I'm in the process of doing this, but are there any other "economical" options before I blow the car up??

Hhmm NOX huh? I have a 91 Lumina that (3.1) that had troubles with that (actually replace 2 CATS because of it, still failed). Somewhere in the world of the internet I found NOX could because of carbon build up (maybe but not exclusively with EGR) . The NEW garage I took it to (with that info) ran about a dozen carbon treatments on it and finally got it to pass (barely). Just a thought, I don't know if this is the case in your vehicle. Good luck

Nox is a byproduct from the engine running the combustion chamber too hot. Decrease the combustion temps and it will pass.