Hey guys its been a while. but im in a bit of a pickle

im getting a check engine light ever since i hooked up my zex dry nitrous system. i keep pulling the same code: p0401 insufficient EGR flow.
and i cant figure out what to do about it. HEEELLLLLPPPP!!!......please.
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2004 GT current mods : CAI, flowmaster "loudmouth" mufflers. BBK Short throw shifter TB and UDPs, zex 125 dry shot nitrous. Next mods: Roush body kit, brakes, suspension, paint, light bar, headers and full exhaust. $3600