Dude, is this a black 97 GSX? How long have you owned it?
Here I am giving you advice about my old car and I think that you have it! Woowoo! I was just missing that car today!!! It had the fuel pressure gauge mounted on the fuel rail, and I recognize that CAS and the one wire that swanny helped me patch together on its plug. And the wideband gauge in the dash, its a PLX right? Also an ebay strut tower bar?
Just pull the power to the negative terminal of the ECU for a minute or two, plug it back in, and this will go away, just like I said before
Where do you live, can you come take me for a ride in my old car?