It seems the initial setup of your system is off — follow the instructions here:
https://nineelevenheaven.wordpress.com/the-911-sc-3-0-engine-with-catalyst-and-lambda-control/
Don’t just adjust the mixture screw — the resulting duty cycle at idle should fluctuate around 50–55%, and while driving at higher RPMs it should fluctuate around 40%.
Everything is explained in the link above.
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Third, I disconnected the O2 sensor and verified voltage coming from the sensor with a volt meter, I was seeing a pretty steady .8 VDC. I was expecting more movement.
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f the sensor is disconnected, the regulation is off, which means the lambda is far from the sweet spot where the voltage would normally fluctuate. In your case, it’s steady at 0.8 V because the initial mixture setup is too rich.