Why would you want to defeat them? Sure, back in the mid-late '70s when they started this crap and none of it really worked worth a flip, I could see it. But today, modern emissions equipment works transparently, you'll never even notice it in operation when it's working properly, and it's more reliable than ever. And (gasp), some of this stuff even makes the engine run better and last longer.

 

PCV for example

I could do without EVAP tho

 

Well true... I suppose... but I find it funny that a buddy of mine does weird stuff to his Ranger like remove the o2 sensors and like the pcv valve and stuff.. that truck runs choppy as heck. But he says it's got more power.

But when he goes in for inspection, he puts everything back on and drives until the truck is "Ready".

 

My guy here in texas checks my a/c for its cooling abilities and I am on my way.

 

In mass since i am obd1 he checks the horn, the headlights and throws her on the dyno and does a sniff test then im out the door.