O2 Sensor low voltage DTC error P0131
Thread Starter
Teching In
Joined: Aug 2016
Posts: 9
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O2 Sensor low voltage DTC error P0131 I am in need of some assistance in troubleshooting my drivers side front o2 Sensor.
Car runs good and I have been having this issue off and on for a while now. I can reset DTC and it will stay off for 5 minutes or 2 hours then come back.
Running long tube headers with Vband clamps (sensors are in collector areas) no noticeable exhaust leaks.
What have done so far in troubleshooting.
HP Tuners shows 0 Mv on drivers side o2 sensor 450Mv on passenger side.
Fused power is supplied to both front sensors from the same fused feed. There is 12.5 volts at the power wire on the sensor plug for the sensor that's generating the error.
Swapped both front sensors side to side and the problem remained as B1 S1 0 volts
Swapped both O2 sensor extensions and the problem remained.
Cleaned and dielectric greased all connectors from ECM to O2 sensor connectors.
Not sure how to test the switching in the ECM without damaging anything ( to much load or amperage)
I am assuming the low voltage reference is the sensor reading being delivered to the ECM and not a power supply issue with the harness or 12V power feed.
I just installed a ZL1 supercharger and am waiting to build a tune file but I don't want to proceed with tuning until I get this issue resolved. I assumed it was caused by lean or rich mixture before because of the random errors (issue was present before the upgrades took place)
Any help would be appreciated as I am about out of ideas.
Car runs good and I have been having this issue off and on for a while now. I can reset DTC and it will stay off for 5 minutes or 2 hours then come back.
Running long tube headers with Vband clamps (sensors are in collector areas) no noticeable exhaust leaks.
What have done so far in troubleshooting.
HP Tuners shows 0 Mv on drivers side o2 sensor 450Mv on passenger side.
Fused power is supplied to both front sensors from the same fused feed. There is 12.5 volts at the power wire on the sensor plug for the sensor that's generating the error.
Swapped both front sensors side to side and the problem remained as B1 S1 0 volts
Swapped both O2 sensor extensions and the problem remained.
Cleaned and dielectric greased all connectors from ECM to O2 sensor connectors.
Not sure how to test the switching in the ECM without damaging anything ( to much load or amperage)
I am assuming the low voltage reference is the sensor reading being delivered to the ECM and not a power supply issue with the harness or 12V power feed.
I just installed a ZL1 supercharger and am waiting to build a tune file but I don't want to proceed with tuning until I get this issue resolved. I assumed it was caused by lean or rich mixture before because of the random errors (issue was present before the upgrades took place)
Any help would be appreciated as I am about out of ideas.
You probably cut and/or burned some wires during the header install. The 450mv reading on the other side is a default that you get with no signal at all. The 0mv reading is probably a wire shorted to ground. If the problems stayed on the same side after switching sensors, this is 100% a wiring problem.
Thread Starter
Teching In
Joined: Aug 2016
Posts: 9
Likes: 0
You probably cut and/or burned some wires during the header install. The 450mv reading on the other side is a default that you get with no signal at all. The 0mv reading is probably a wire shorted to ground. If the problems stayed on the same side after switching sensors, this is 100% a wiring problem.
I jumped a 1157 lightbulb across the red and yellow sensor wires expecting to see some on/off activity but got nothing with the car running.
I can get 12.4 Volts probing the power feed so I think I have a bad ground going back to the ECM or the ECM is not switching the ground.
