Optimizing Sensor Performance with Normal Readings A Practical Approach

When I was graphing the front O2 sensor the voltage readings were steady around 18000. ... Was car already at/past normal operating temp (ramp-up)?. My understanding is that when the car is running and up the normal operating temperature, the sensor generates a voltage and ideally this should be around 0.45 ... Oxygen sensors will run from almost 0 volts up to around 1.1 volt. I'm not sure why it's reading over 2 volts, but some aftermarket diagnostic tools can be a ... Anyway, the downstream O2 should be somewhere in the middle (0.45V) if the cat is still there. The AF sensor though, as per the FSM, fluctuates ... Generally speaking, yes. Conventional O2's in an upstream position will switch. Downstream sensors will USUALLY hang around 600-800mV if the catalyst is ... It will read very rich almost all the time in around the 0.845v range give or take a little but then if you just let it sit it will drop down to 0.1v or below ... ... sensor is properly detecting the PCM's normal, frequent fuel mixture alterations. For now, forget about the downstream O2 sensor ("B1S2"). When I often see a more or less constant reading on those tools, I expect the DME to be upset, yet it often isn't. I expect to see readings ... O2 sensors should cycle continuously between 0.2v to 0.8v and back to 0.2v about once per second. 2.67v isnt right. Could be a vacuum leak, ... The normal readings are 18 to 19 in. There must be some issue with the source vacuum or a voltage drop to the required circuits for that sensor to work.