P0130 O2 Sensor Circuit Malfunction (Bit alternates 0, 1)

[Blockis]

Hi guys.

I am having issues with a P0130 code. So the code itself is a circuit malfunction, but I replaced the O2 sensor twice, both times resulting in the code (even after clearing twice). I was looking at measuring block 30 and noticed that the first bit for B1S1 O2 sensor was alternating between 0 and 1. Even after 5 minutes the activity continued. Is this indicative of a wiring harness issue? I've attached the screenshot of me looking at the measuring block, and the bit that was alternating 0 and 1.

Thanks for any help!

[old guy]

The display zone 1 (red arrow) indicates whether or not the O2 sensor heater is on. It's normal to see it cycle on and off.

[Blockis]

The display zone 1 (red arrow) indicates whether or not the O2 sensor heater is on. It's normal to see it cycle on and off.

Ok, so my next theory: would a large enough exhaust leak be capable of tripping the code?

[old guy]

Ok, so my next theory: would a large enough exhaust leak be capable of tripping the code?

Yes an exhaust leak could cause a P0130. And just to assure myself about the 0-1-0-1 I just checked mine and the sensor heater definately cycles rapidly on/off.

[Blockis]

Yes an exhaust leak could cause a P0130. And just to assure myself about the 0-1-0-1 I just checked mine and the sensor heater definately cycles rapidly on/off.

OK, thanks old guy :)

[old guy]

And to add a little more information a P0130 doesn't necessarily mean that the sensor is bad. It means the ECM sees less than the expected voltage from the sensor for too long of a time period. Normally the sensor generates a voltage signal when the O2 content on the outside of the sensor is lower than the O2 content on the inside of the sensor. The inside of the sensor is vented to the outside air.

If you are running really lean or have an exhaust leak adding air into the exhaust stream the O2 content in the exhaust is close to the outside O2 content and the sensor doesn't generate a signal. As previously stated the sensor creates a voltage signal from the oxygen difference on each side of the sensor. So lots of oxygen on both sides (Lean condition) equals no voltage. Lots of oxygen on outside, none on the other side (rich condition) equals more voltage. So what you may have going on is a lean condition causing the oxygen sensor to never change and as a result the ECM is setting the DTC P0130.

[Blockis]

So I found that one of the bolts connecting my 034hfc to the downpipe came out and was causing the exhaust leak. Had a shop get a new bolt in there (also, are there nuts that can be put on these bolts? because I don't want the bolts to fall out again...) and she quieted down. However, I cleared the code and it returned 10 miles after. So I need to find out what's causing the lean condition? Any tips on things to check out first? Vacuum leak? MAF?