Not having a cat can potentially set a code, and thus, turn on the light. However, if you get a couple spark plug 'non-foulers', drill one out so the O2 sensor probe fits thru it, screw it into the other one, and then screw the whole thing into the exhaust pipe, it will solve that problem for ya.

On mine, My cat is gutted, nothing on the post-cat O2, and I don't get a code....

 

It'll run just fine. You might notice a pinch of lost low-end if you've got a free-flowing cat-back on there now, otherwise it'll probably improve some. Just do the non-fouler trick HeyYou explained above and you'll be cruisin'.

Please do your best to forget the dire warnings about back pressure being vital to keep the engine from jumping out from under the hood and flying through the window of the pet shop to kill puppies and kittens. The engine will be just fine without the cat.

 

dang i need my low end once and a while, as i pull trailer a couple times a month on average

 

o and btw, wtf is a spark plug non-fouler? never heard of them and neither has my dad

 

Here ya go.

 

That is a nice DIY, but I believe the part # is wrong for our trucks. You need HELP part # 42002. I'm looking at the card from the ones I used on my 98.

 

Good catch! I haven't had to do this, so, wasn't sure on the part numbers. Just wanted to give him an idea of what it was all about.

 

Well, I just did some research. The only difference is the 42009 is a gasket seat, compared to the 42002 which is a tapered seat(either one will work). The part store only had the 42002 in stock and 18mm was all I was concerned about at the time. But hindsight being 20/20, since the o2 sensor is a gasket seat,had they had those instead too, I would have noticed and bought the 42009's.

 

thanks for your help guys, sorry for stealing the thread, i pulled my cat off and gutted it and reinstalled, about 50 miles and no CE light (knock on wood), and sounds better than i thought i would ever hear it,

 

Now all you have to do is replace the plenum gasket. That's why you have been having cat(s) problems.