I know O2 sensors are supposed to fluctuate up and down, but after reading that O2 document on Mark's site it seems mine is staying too low too long.
Any ideas?
That was just 2 seconds at idle so not that big a deal, everything else was stable like RPM blm etc...during that time.
Now that you have a heated O2 it should not happen, but I have still seen the heated O2 cool at idle on conversions because of a couple things. One was the heated O2 is placed so far down the exhaust, like in the header collector, that it just cooled down below the 600 degrees needed to work. The header dissipates a lot of heat, ceramic coated headers keep heat in and work better. The other reason and one that brings up all sorts of issues on conversions is the charging system. EFI cars have better alternators that charge at idle, old carb cars and charging systems need some more RPM to charge. EFI needs a good steady supply of minimum 12 volts. So in looking at your short burst of data it looks like you were idling awhile and battery voltage could be dropping, as it drops so does the voltage to heated O2 sensor also drops and heats less. Also the longer you idle heat in exhaust will lower. But for now I wouldn't worry about it, it rebounded and started to cross count again.
How hot should a 3 wire get when just hanging in the air? I double checked that I was getting 12v to the sensor but it didn't seem like it was getting all that hot.
Not much like keitha said. I checked mine on the bench and the outside temp got to around 120 degrees, you could still touch it. But that's just radiated heat from the element inside.
One more bit of information I came upon!!
My motor has votec heads and they take a longer spark plug!!
Man you don't want to here how many hours I spent trying to make one conversion run because the spark plugs were to short!!! They were Accell plugs for headers, pulled them out and they were only half way into the threaded hole. Went to parts store and got what factory called for and they were twice as long and would put the end of plug in cylinder where it should be! Asked him to look up the Accell equivalent and he went and got one. Sure enough way to short.
My recommendation for plugs are the ones the engine came with. If the car had points but later year had electronic ignition and same heads look up the electronic plug and check that it is same size as the correct one that came out of the head. It must end up in combustion chamber, not in threaded hole. In your case Vortec heads had electronic ignition so get what it calls for. Don't waste your money on all these expensive new snake oil improved spark plugs
I always solder in a connection, if needed in the O2 wire with no issues. So I don't think that is your issue. I'm sure there's an electrical law that would effect length but not in your case, guys extend O2 wires all the time from stock to reach header. Even the factory runs a wire on new cars all the way back to behind the CAT on OBDII cars.
HTH!