What I'm reading so far is... the change in testing will be nationwide. It happened a few years ago in some other states. Illinois went to the new test sometime last year. Lots of threads (on other forums) with people freaking out because they were failing (especially if the cars were daily drivers)! The vehicles fail because of sensors being turned off in the tune. Sounds like the tuners might have found some workarounds, but they can't be discussed on the internet? I left a message with our guy and the guy in St Charles looking for guidance. Luckily I kept the original cats, and if that's all I need to put back on I'm ok with that. Just don't have time to deal with this crap at the moment, I've only put 2000 miles on the truck in the past four years. I was thinking about selling it but now I can't do that because of the failed test.