Exhaust gas re-circulation is what it stands for. Of course there's probably some other technical term for it but basically, it does what the name says. Exhaust gasses are sucked into the EGR(via hole in the bottom of the EGR which is connected to the engine) and re circulated back into the intake manifold. I don't know about you, but wouldn't hot exhaust gasses be BAD for the air intake, which is supposed to be as cold and oxygen filled as possible? The engine's byproduct is carbon monoxide(or dioxide?)... would feeding an engine it's own byproduct be good for it?? Do you eat your own byproduct??? I sure hope not! So what do you do? Remove the EGR and cover the hole so exhaust gasses aren't sent back into the engine.
It's hard to see in the picture, but look inside the circle between the two Nitrous lines and there is a black valve sitting there with a yellow line hooked up to it. It's easier to see on an engine that's not all cluttered with NOS plumbing everywhere. Basically the EGR has a plug, a vacuum tube, and two bolts holding it down. Unbolt the EGR and unplug everything attached.
1. Cap off the vacuum tube. Either get some tubing caps at a parts store or plug it with a golf tee.
2. Leave the plug alone. Zip tie it out of the way.
3. You can see that you have a hole left over where the EGR went. Get a thin sheet of metal and some tin snips. Set the metal on a table and put the EGR on top of it. Trace the bottom of the EGR on the metal and cut the shape out with the tin snips. This is your cover for the hole where the EGR went. Drill two holes that correspond with the holes in the EGR. Now, get the EGR bolts and bolt the plate down over the hole where the EGR went. Now you won't have exhaust gasses being shot out of your engine nor back into the engine via EGR. Your car might trip a check code but that's life. The check engine light is designed to detect errors in the emissions equipment and since you're removing some of the emissions equipment, it might trip a code.