Just installed it, and getting some interesting readings. At idle once warmed up it transitions smooth and slowly from lean-rich. When running 55 mph it seems to go nuts. It lights up the "STOICH" range kinda like a strobe light, back and forth all of the lights. If this is normal it's all good then, but if it should be more steady then I've got some work to do. I'm using an AC Delco 02 sensor. 92 RS TBi 5spd.

Al

 

Stock engine? Properly tuned it should dance around stoich at all times. Occasionally such as DECEL and Lean Cruise it will drop all the way to the lean side(red and off). Some calibrations idle in open loop and slightly rich(high yellow-low green). PE mod (WOT) will result in rich a/f mixtures (green).

 

yes it's stock. When you let off throttle completely it stays rich then 3 seconds later it goes lean (mid range on guage). I read the instructions and expected it to stay near the stoich/rich area more than it does.