[Shotimes] Help with lean condition

[Mark Helpinstill]

I am extremely frustrated today - driven to shop for new cars.

Having trouble with my 94 MTX.  I failed emissions for high NOX (by only 10%),
so I replaced my original o2 sensors (175K mi) with the Bosch 13942.
Restarted and after going 10 miles got a check engine light.  Pulled codes and
got the 172 and 176 O2 sensor codes.  Pulled new o2 sensors and bench tested
using the shotimes procedure - both failed to show decent voltage change.  I
returned them to autozone and got replacements today.  Just installed them and
no longer getting the CEL, but with the code scanner still getting the same
codes, plus engine running getting code 16 (does not exist apparently).  Code
scanner is a high quality autoxray unit.

Checked for vacuum leaks and cleaned MAF.  Still getting the same codes.  Any
suggestions before dropping the car at a shop?  I reinstalled the original
ford O2 sensors and get no codes.  It will likely cost $200+ just to get
someone to look at it, and likely tell me nothing.

Bottom line - I replace a good part with known good parts and now I have
codes.  It seems likely that I have had a lean condition and the new O2
sensors are more accurately reflecting that with a code.

If no one has any ideas - what about suggestions for a cost effective shop in
central NJ?

Thanks
Mark