yeah, it will tell you rich or lean, but it won't give it to you in real time, nor will it tell you by a readable figure of how much. But like alerored says, it's only function is a pretty light show.
As for the wire that connects to your O2 sensor.......
I dont know which one your instructions tell you to tap into, but here's the wire colors and what pin connection they're in at the PCM:
Connector 1 (Blue):
12 - Tan - HO2S Low Reference sensor 1
28 - Tan/WHT - HO2S Low Signal (Bank 1 Sensor 2)
Connector 2 (clear):
10 - PPL - HO2S High Signal Sensor 1
11 - PPL/WHT - HO2S High Signal (Bank 1 Sensor 2)
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