P1500 e P0130 Codes

[rmileo]

My CEL turned on and i have 2 codes:

P1500 - Generator FR Terminal Circuit Malfunction
P0130 - O2 Sensor Circuit Malfunction

I replaced the O2 sensor, but the problem continues. When i erased the codes, i drive some miles and the CEL turns on again, always with these 2 codes.
One strange thing: at idle, the light of my a/f gauge doesn' t move. When I blip the throttle, the light move up and down. The a/f gauge works normally when i drive.

My car is a 95 GST. The mods are basically: 3' Exhaust, 1G head and 1G intake. Can someone help me ?

Sorry for my bad english. Tks !

 

[screwdgie]

Thats normal, at idle, your gauge shouldnt move. On my logger at idle, i usually see a steady .04v.