Ok volks, here it is

On a 3 wire sensor, does the heater element always stay on, or does the ecu
or other magical process stop the heating at some point in time or some
point when the sensor is hot enough?

I'm thinkinkg of retrofiting my 1984 1.9L one wire setup to the 3 wire job,
the thought being that it would heat up faster, idle better, get better
econonmy, smog etc.  Is it worth it, or is it  a waste of time, money,
stress, effort, patience, dirt, grease, rapped knuckles, spouse's tolerance
etc.

Thanks

Alias Fred aka Bleu schtroumpf