Hi I have a question about the reading at post two and three, after the car has warmed to op. temp. I continue to get a constant reading of 50.2 and 50.3%. I have moved the fuel mixture in both directions from very lean to black rich and no reading other than stated. the ox is new and no check eng light. am I looking at a new ECM? thanks in advance for your thoughts.

I'll give this a whirl, and if any thing else it'll btt. A fixed 50% ratio on some cars indicates a o2 signal or heater problem. What are you trying to cure with the new O2 and the afr adjustment?

had a check eng light, so I replaced the ox,
then I had to go to ballence the afr as it was so very rich, I normally do this with my guages( digital meter ) and could not get the type of reading I am use to seeing.