98 O2 sensor wiring diagram
Headers and Hi flow cats are installed.
Signal wire color?
Thanks
I always appreciate your input Bill, if you could look at the schematic posted couple posts earlier, is it the purple/white wire that is the signal wire for the front (before cat) on the drivers side.
Thanks for your input Bill as always!
If the gauge only has 1 sensor wire then you could try grounding the low wire to the same spot you ground the gauge. It would likely work but unhook it if the car quits running correctly.
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If the gauge only has 1 sensor wire then you could try grounding the low wire to the same spot you ground the gauge. It would likely work but unhook it if the car quits running correctly.
The Purple & Purple/White wires are the signal wires.
The HO2S Low Reff return (circuit ground) wires TAN & TAN/WHITE wires are the signal return path for the circuit. All low voltage (millivolt) signals use discrete grounds ( Low Reff) to complete the circuit signal paths.
If you try to use a chassis ground for the return path, , it could very well cause bad readings or sensor issues due to the difference in ground potentials.
Something else to check . I find this BAD in a LOT of C5 that I come in contact with. That is the heater supply voltages and the ground circuit poor resistance for that circuit...
The sensors must have a properly operating heater circuit. If you look at the heater circuit fuse, you will see that is a Hot In ON supplied circuit. That voltage comes from the IGNITION SWITCH and that switch contact is well known to carbon up and supply poor current/voltage to that circuit..
Same goes for the circuit GROUND (G-105 thru Slice pack SP-122).
If it were me, I would read the voltage on the fuse test slots on top of the fuse and then check the resistance of the heater circuit from the O2 connector to battery ground.
Bill
The Purple & Purple/White wires are the signal wires.
The HO2S Low Reff return (circuit ground) wires TAN & TAN/WHITE wires are the signal return path for the circuit. All low voltage (millivolt) signals use discrete grounds ( Low Reff) to complete the circuit signal paths.
If you try to use a chassis ground for the return path, , it could very well cause bad readings or sensor issues due to the difference in ground potentials.
Something else to check . I find this BAD in a LOT of C5 that I come in contact with. That is the heater supply voltages and the ground circuit poor resistance for that circuit...
The sensors must have a properly operating heater circuit. If you look at the heater circuit fuse, you will see that is a Hot In ON supplied circuit. That voltage comes from the IGNITION SWITCH and that switch contact is well known to carbon up and supply poor current/voltage to that circuit..
Same goes for the circuit GROUND (G-105 thru Slice pack SP-122).
If it were me, I would read the voltage on the fuse test slots on top of the fuse and then check the resistance of the heater circuit from the O2 connector to battery ground.
Bill
This is what the Gauge literature shows for installation as far as 3/4 wire hook ups , still as you can see that the purple wire from the guage gets tied into the O2 High signal (picture added below also),
Also am I correct that Bank 1 sensor is before or the front sensor, so according to your folks info then I would run the gauges purple wire to the Purple/white and the ground from the gauge would be tied into the Tan/white wire of the O2 sensor..so I will splice in another ground lead from the ground wire that was going to be grounded to chassis , and run a lead to the Tan/white . ( or a seperate ground lead from the gauge to the sensor and not the chassis)
Thank you Lionel and Bill, much appreciated, just trying to get the info correct since my son in law will be doing the back bending work ,lol
Last edited by Pizzano; Jan 28, 2017 at 11:55 PM.












