Not sure if this might be helpful to anyone but I took my 95TT into be smog tested per DMV request and it failed with 550 ppm NO for the 25 mph test (spec value is 500 ppm now down from 700 a few years ago). They are asking for a test every two years now. The EGR system has been retained exactly per OEM. I checked the electrical resistance of the solenoid, the electrical resistance looking back into the ECU and the vacuum operation of the EGR valve and all was good. I recently chromed the plenum and I discovered today that I had reversed the EGRC (EGR control solenoid) vacuum lines that go to the throttle chamber and the air duct pipe during the re-assembly. These are the two small hard pipes that run the length of the passenger side of the plenum that have hoses connected on either end. One end goes the EGRC and the other to throttle body and air duct riser pipe. I had it re-tested and it came in at 17 ppm NO for the 25 mile test and passed of course. A dramatic difference. Just a data point for you all. Hope this helps you California Z owners. If you live in the LA area you can appreciate the effect of pollutants when you see the grey haze around the LA valley every day. It rises to the top of the mountains so I am glad to do my part to keep things green.
Follow Ups
California Smog test / EGR system - zman0301:37:25 09/11/16
