So just got a call from the mechanic-- looks like he found:
 the AFM needed to be adjusted 
an exhaust leak at cylinder #4 ( loose bolt )
idle speed too slow 
and... the popular vote... the oxygen sensor was not working. He said it was broken- That was the second oxygen sensor in  6 months!

 we figured the AFM needed to be dialed in, and we couldn't do that without the proper equipment- so we're  happy that we  took it to him.Seems like our rebuilt t/b  solved the air leak.
 We'll pick it up Tuesday :) Can't wait!
 So far very pleased with George at Porbug_ thanks to all who recommended him!

thanks, Susie