91 Tracker CEL light glows

[ORF-tracker]

'91 geo tracker 4WD Auto. So my tracker acted up the other day driving and the RMP guage went up and down and car stalled and then the clicking sound from the Fuel Pump relay. I got a CEL code 12 at that time, but it would start, clicking sound and eventually stall. I got towed home.... So I bought a new fuel pump relay. Now I cant get the CEL to go off. Ive pulled the dome fuse and negative cable. Ive disconnected the NAG switch.

Is my ECU dead? I havent pulled it yet.

thanks!