You need a little more details on what didn't pass about the emissions, I am sure they would tell you what failed it.
But there is a whole host of things that could cause this, bad O2's are one, if it hasn't had a tune up in forever that could be also, not sure of your locations and how strict they are where you are at.
As O2 sensors age they tend to get lazy and can tell the pcm to make a car run richer or leaner when its not needed. This wont always throw a code. The recommended change interval is 100k iirc. It could also be other problems like the cats, without knowing which part of the test it failed its hard to say.
nope take them back ac delco only,and that hose you can actually eliminate that whole system so i suggest you start reading the stickies cause there is a lot of info and very descriptive to what is needed so you can get it done on your own but do not for your sake use that bosch bull**** your car will run like crap i know first hand...
it runs good now i just replaced the opti spark because when the car warms up it shuts off it didnt do it today with the new distributor in it new distributor and opti vent harness, just the right size hose keep heating and cracking up it get hotter that the other intake hose. Never did a air pump delete i wanted to keep it on there but the hose keep cracking up i wanted to know if anyone knows y it does that. i thought it was the metal piece to the hose does that goes bad!!!! is that a o2 sensor problem