O2 sensors wiring diagram needed

1989 CHEVROLET 2500
170,000 MILES • 5.7L • V8 • 2WD • MANUAL
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TY1184
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I have a o2 sensor and cannot route the wire. It’s a purple wire. I can follow it from my exhaust flange before the catalytic converter up to the motor but then the connector part is just there not connected to anything. Where do all the o2 sensor wires route to? I cannot find a good color schematic diagram for any wiring for this truck.
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Sep 5, 2020 at 4:13 AM
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DANNY L
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Hell, I'm Danny,

Yes, the purple wire is the o2 signal reference wire. The wire connects to the o2 sensor and originates from the ECM. I've attached a diagram below.Hope this helps and let me know if you have any further questions on this. Were you able to locate the sensor in the exhaust pipe? Thanks for using 2CarPros.
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Sep 5, 2020 at 12:52 PM