You should always try the least expensive tests and most common ones first, IMO.

A simple scan will tell you if your O2 sensor is bad. Seeing as the O2 is the last line of defense that normally corrects for rich/lean conditions, that is where I would start.

Many an AZ or Advance have scanners that can identify a bad sensor for you.

EDIT:
How rapidly was the O2 switching back and forth?

EDIT 2:
What brand O2 sensor did you use?

Your O2 Mv'* were at 800. That'* rich. Very rich actually.

Was the car up to temperature at the time? What brand of O2 sensor did you install?

its a denso, the mv varied rapidly, but was mostly hanging around 800. The O2 switch back and forth rapidly and then slowed down a little, went to lean and about 10 mins after the idling it was rich for about a min. And the car was warmed up, 205 to be exact.

Ok..once up to temp. The O2 mv'* should toggle between say 700 and 100 up down up down..a couple times a second or so. Sometimes it'll hit 800-900 and others it will hit 50-100. It'* jumps from high to low and rich to lean.

What he said...

That'* what I was getting at.

If that was a new O2 sensor you put in and it'* not acting just like how Bill said, then you need to take it back and get a new one. Sumpin'* not right.

And ....Like Crocodile Dundee above previously mentioned. If the O2 is bad..it'* possibly causing your cat to go belly up.

ok I'll return with results in a week or so. I'm going to go ahead and "thouroghly clean my TB and and throw some sea foam in my vac since I have to replace the O2 and CAT anyway. Then I have to hustle up some money for a CAT. I just blew all my money on that Hifonics amp.

You bought an amp when your car was running like crap?

Cough...on topic please.. cough (Pwned)

actually I bought it for my other bonnie (the one thats running in tip top shape) and I was going to sell my current sound system but I passed on it. The other bonnie was a project car, but I guess I'm going to fix that one up as well. Another reason I got the amp was that it cost me $300 and some other services.
I just couldn't pass up that deal. I also wasn't spending anymore money on that car until I found out the root of my problem, but I love both my cars, I just wish they were supercharged. Maybe I'll trade both of them for a 1999 seei, whcih is what I really want.