sup guys...... i did this on a fed spec 2k on the o2 sensoron the cat....

i bought the o2 sim from cattmann, the colors on their o2 sim are as follows...

black = ground
red = +12 volt
yellow 1 = first signal wire
yellow 2 = second signal wire

now i connected mine before the o2 sensor harness under the car, it was straight forward

black to black
red to red
and
one of the yellows to the white wire, but remember you must cut, NOT SPLICE the white wire and connect the sim's yellow wire to feed back to the ECU.



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