When starting car cold, seems to idle somewhat erratic. After car runs for awhile it will not idle at all. Revs fine but will not idle.

I just replaced the entire exhaust, but I was having this problem just before I started the new exhaust. I'm thinking maybe O2's but do not know.
Any suggestions?

 

I have exactly the same problem! I have changed both IAC and EGR valves, checked all vacuum lines and connectors, but still the car won't idle.. I even changed both 02 sensors, but those had no effect on idle.
If you find solution to your problem, please let me know! Send me a private message or answer to this thread so I could fix my car also
-Mikko, Finland