1994 Ford Thunderbird check engine light comes on at startu

The Data Link Connector C2012 is located behind I/P, below glove box. https://www.2carpros.com/kpages/auto_repair_manuals_alldata.htm

thank you so much! that did it. now the code read troubleshooting p0402. egr system fault. the ecm has detected too much flow on the egr system. probably cause

1. egr valve stuck open
2. failed egr pressure sensor
3. failed egr valve

now right before this started happen my wife darn near ran it out of gas. would that have something to do with it? is this something i can fix/test myself, or should i take it to a shop?

now right before this started happen my wife darn near ran it out of gas.

It has nothing to do with the fuel system-I strongly recommend you briing it in after you clean out the EGR valve and test the DPFE sensor and it continues-

Most cars these days that have a check engine light are susceptible to the problem of a loose gas cap causing the check engine light to come on. If I forget and drive away from the gas pump with the gas cap loose, the check engine light will come on the next time I start the car. When I put the cap back on and tighten it (enough so that it clicks a few times), then the light will stay on for several more starts of the engine. After a while the system seems to realize that this is no big deal and the light goes out on its own. There is a way to clear that by resetting the service codes, but for the average driver, it is easier to just let it be and see if it goes out after around a dozen starts of the engine. If it takes longer than that, have the dealership reset the codes so that the light will go out and the system can capture the next 'real' problem, notifying you with the check engine light.
Safe drive.