Help!!
Ok I'll tell my story from the very beginning....Here goes....
For a few weeks, I noticed a very small, kind of rattling noise coming from my exhaust. For a while, I thought nothing of it. One day, I went out to start it, and it finally started but ran horribly. It wouldn't idle at all and would die below about 1600 RPM or so. Also, the whole exhaust was shaking like you wouldn't believe and had a very loud rattle to it. I had to drive home constantly revving it up so it wouldn't die (which was very embarrasing given the sound of it) I talked to several knowlegeable people, and we all came to the conclusion that my cats were clogged/messed up some how. I went to the exhaust shop, and after hearing the cost of 2 new cats (over $300..is that right?), I opted to have the guy just cut off the cats and weld in straight pipe. Sure enough, the cats had ***** of screen rattling around in them. After the car came off the lift, I went to start it and it still ran like crap and couldn't idle. It no longer clanged however. I drove home, revving it up all the time. Keep in mind this whole time the SES light had never come on.(even with clogged cats and bad EGR) The guys at the shop thought it was my EGR valve, so I ran it up to a shop the next day and had it plugged in, and it showed the EGR code. He replaced the EGR valve, and it ran ok. For the first week or so, the SES light never came on. Now, the SES light comes on after 3-4 miles of stop-and-go driving.
Is this happening because I have no cats or for another reason? Also, is it possible to pinch off the A.I.R. tubes that used to go to the cats without damaging the pump or anything else? I would prefer that if possible, because now that I have no cats the sound of the A.I.R. is kind of annoying. All I ask of the car is that it runs good without the SES light coming on.
Any help would be greatly appreciated

(yes I read the AIR post, but didn't find what I was looking for)

 

What code is it? Read the code for insight. I'll wager it is probably an O2 code. My runaround car is a 1991 Lumina Z-34, the factory mufflers finally went. $400 bucks a side for GM units. Went with aftermarket high flow units. First, it flunked emissions. Never did before, it was always at the low end for CO and HC. Also it randomely threw an O2 code. Problem was too little restriction in the exhaust. My guess is that without the cat the exhaust is too cool throwing the O2 out of range. The O2 can compensate for minor variations in operating conditions but without the cat it may not be staying hot enough. If it is an O2 problem you can fix it rather easily. Get a heated O2 sensor. They are more money but if that is the problem it should cure it and keep the SES light off. Otherwise go back to running a cat. Obviosly you are not worried about emissions, why not just take off the AIR injection system completely. Plug the manifold holes and just take it all off. You will be surprised how much room you have to work after it is all out of the way.