Well to start off i just got done doing a motor swap into my 88 5 speed I installed a new narrow band auto meter air fuel gauge just to make sure i was not going to go lean for any reason. And found it would not work so i hooked up my multimeter set to mv to what i assumed was the signal wire the white wire at the three wire connector above the cps. i had nothing. So i replaced sensor with a bosch universal o2 sensor into the exhaust elbow and found i was now getting 625-650 mv at idle. When i went to hook it up to my engine harness connector all the sudden i no longer had any voltage then i would unplug it and then i would have voltage again now the car has a really low lopey idle. Is the the white wire on the engine harness the signal wire? the two other colors are red with a black stripe and is battery voltage when the car is running I would think for the heater circuit and the other is black with a red stripe. Any suggestions would help. Also the codes that came up are 31,32,42,51.