I did multiple things at once so I really can't say what really affected the change the most. At least with the tune:

1. I went ahead and reduced the timing advance by 50%.

2. I turned the...

Just to close this thread; I got the car to pass.

http://i3.photobucket.com/albums/y94/paulo57509/lumina/2016%20emission%20test_pass_cropped_zpsdjbxufcw.jpg

Saturday afternoon I removed the plenum in order to get to the injectors and fuel rail.

I measured the resistance of each injector and got the following values. Temperature of the injector...

I removed the EGR and jumpered the terminals between 12v and ground. All the solenoids/pintles open. I confirmed that the EGR valve passages are clear with compressed air with the pintles opened.
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Robert, Thank you for the feedback. I've already been following your diag path but in a different order.

I've replaced the O2 sensor first (I had one on the shelf) with no change.

I hooked up...

My old '92 Lumina (3.1L V6, Auto, 201k miles) failed its biennial emissions test. The results are below.
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