Hey man. Ive been having the SAME problem - exactly. Although mine is not as bad. I just recently had a huge breakthrough. Check your ground connection. Make sure the ground cables that connect to the starter/bellhousing have a good solid conenction with your battery. My engine had terrible grounding, after that it started much much better. I still have a sensor out I believe, and my car runs very rich nad has slight hesitation problems- but grounding the engine well gave my car a new heart it almost feels. SInce youve tried so many things, I strongly recommend a ground kit or at least that you look into that.

Ive replaced so far:

Map sensor
Plugs (which keep fouling cause it runs rich)
Plug wires
Front 02 sensor

IOm trying my PCV valve, TPS, collant temp and IAC soon...

Man..it sucks..