O2 sensor

[Sick Puppy]

Is the OEM O2 sensor on a '84 SVO 3-wire or 4-wire? I did a search here and couldn't find anything.
I looked on RockAuto and the Bosch one they list is a 3-wire but I want to verify for sure.
Thanks, Paul

[brsvo]

Paul the only links I found for O2 wiring say 3 wire. I don't have an 84 anymore so I can't go count.
http://www.svocop.com/forum/showthread.php?2342-Electrical-connectors-amp-fasteners&highlight=sensor

[MikeFleming]

84 used 3-wires to the sensor. The "turbo outlet elbow to - turbo to compressor housing ground stud wire" is path is the fourth circuit path. Later cars (sometime during the running production for 1985, before the square intake/PE/85.5 series) they switched to single wire - no electrical heater.