A couple of years ago my cat was all plugged up and a buddy of mine straight piped it. When he was done, no CEL's at all. Is this common or is it just a fluke thing with my truck? Both O2 sensors are still in and I haven't done any mods to anything in regards to this.

not sure why it matters it its just an off road truck?

well its mostly an offroad truck but occasionally it see's some road activity. I'm gonna keep it registered an i'm gonna keep the state inspection (for texas) which means i can't have a code saying the cat is bad.

Try the non fouler fix before you go spending the money for a sim.

is this it zman?

http://www.autozone.com/R,609/initia...ductDetail.htm

Yes, you need 2 of them. Drill one out with a 1/2" drill bit and tighten it onto the O2 sensor.Take the other one ( not drilled out)and screw it into the pipe or onto the one you drilled out.Use some anti seize on all the threads too. And btw, there is already 2 in the package for that part #.