The 3-wire heated sensor offers accurate O2 measurements at times when the
exhaust gas is cooler than normal such as idling or decelerating but would
not be advantageous to you unless you are using a monitor to make fuel
3-wire sensors have 2 blacks and 1 white wire with the white being signal
and the blacks are power to the heater, the heater is bi-polar and does not
care which black goes where as long as 1 is grounded and 1 is wired to a
power source that is hot when the ignition is on.
I use a 3-wire sensor with a Halmeter AF-30 monitor on my Scottsdale and it
has enabled me to tune the carburetor for optimum power across the entire
rpm range. (950 to 6500 rpm)
'79 Chevy K-10
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