dreamscape

i own a 1989 mazda rx-7 gxl. my engine check light turned on and i'm noticing a decrease in power. i've done this before, getting the codes but it was like five years ago. i forgot. i remembered grounding a green connecter by jumping the wires and counting the number of times the engine check light blinks but that is all. i don't remember how to ground the green connecter located near the battery. there is six port green connecter and a one port connecter next to it. i need help. thank you.