Hi All, I have not posted on the Org for like...Forever (March 2007...WTF!) I have been running a Custom Enterprise Y-pipe (along with other mods) for the last 5 years and always wondered what would happen when it finally came time to get the dreaded Washington State Vehicle Inspection emissions test.
To those of you who may not know, the Y-pipe eliminates the main catalytic converter, but our cars still have the pre-cats in the exhaust manifolds. I always suspected that my car would pass w/o the main cat and...(long story short) no problem. We are lucky that there is not an oxygen sensor behind the cat, you can remove the cat and the EMS doesn't know (or care) that the cat is gone. I am not so lucky with my Jetta, but...that's another story.
So, don't fear the Y-pipe! (At least not in Washington State).

 

yeah that third cat isn't monitor, so the only way you could fail would be during the visual inspection.

 

Good thing you don't have headers... lol