Oxygen Sensor Harness

[dwa714]

I recently acquired a '94 K1500, 5.0 A/T. Check engine light comes on when it reaches operating temp. Found that the 3 wire O2 sensor is unplugged. Problem is that I can not locate the harness it plugs into. Anyone know where this might be hidden? Thanks,

[Duelin]

[quote name='DanDaMann' post='1204705' date='Sep 25 2011, 03:52 AM']I recently acquired a '94 K1500, 5.0 A/T. Check engine light comes on when it reaches operating temp. Found that the 3 wire O2 sensor is unplugged. Problem is that I can not locate the harness it plugs into. Anyone know where this might be hidden? Thanks,[/quote]

Dan, check with a parts store and see if that calls for a 3 wire O2 sensor. If I am not mistaken some if not all of those called for a single wire O2 sensor. Also check and see if there is a single wire connector hanging loose near the sensor.

[8.1HD/ALLISON]

[quote name='Duelin' post='1204729' date='Sep 25 2011, 08:48 AM'][quote name='DanDaMann' post='1204705' date='Sep 25 2011, 03:52 AM']I recently acquired a '94 K1500, 5.0 A/T. Check engine light comes on when it reaches operating temp. Found that the 3 wire O2 sensor is unplugged. Problem is that I can not locate the harness it plugs into. Anyone know where this might be hidden? Thanks,[/quote]

Dan, check with a parts store and see if that calls for a 3 wire O2 sensor. If I am not mistaken some if not all of those called for a single wire O2 sensor. Also check and see if there is a single wire connector hanging loose near the sensor.
[/quote]


+1 I would think it should have a single wire, usually purple.

[dwa714]

Thanks for the replies.

I'm unable to locate any unused connectors withing reach of the O2 sesnor. I picked up a new sensor - you guys are correct; it's a single wire.

Where might this single wire branch off from the main harness?

Thanks

[dwa714]

Anyone?

[dwa714]

Found it... Guy at the parts house was wrong. It's a 3 wire sensor; vehicle side connector is on top of the transmission near the transfer case.