I just got my 1994 Chevy tested and failed by 1/10th of a point.  1/10th!!!  They said it was my Cat. Convertor which would cost about $600.00  That's more than my whole exhaust cost.  I was wondering if there is a cheaper way to pass these tests.  I've never lived in a state who did these tests so I have no idea how they work.  I have to say I think it's stupid because my buddy lives 15 minutes away and he doesn't have to get his vehicle tested.  

Change your oil right before the test, and get the truck hot before getting it tested. Go out and drive 30 miles or so, the cats work best when they are hot. Those two things should get you your 1/10th of a point without changing out the cat.  

I'll try that, but now that I think about it, last year my truck was making this weird whistling noise after my exhaust rusted off.  I looked at my 2" pipe that was left behind the cat and the honeycomb stuff inside the cat was stuck in my pipe.  A ton of that stuff came out, so I doubt there's anything left to get hot.  

Yea, but if you're only 1/10th of a point away from passing it's worth a shot right?  

That's very true.  If that don't work I'll put some carbon scrubbers in there to get it to pass.