O2 sensor was replaced twice, buy code comes back

[V1nny]

16514 - Oxygen (Lambda) Sensor B1 S1
P0130 - 35-10 - Malfunction in Circuit - Intermittent
Was blamed on ECU, so ECU was replaced too. Whats next to replace or troubleshoot?

[Mille Bornes]

You're replacing the correct sensor, right? B1S1 is passenger side, front sensor. You'll see it peaking down between the firewall and cylinder head.
I ask because I just checked the ross tech wiki and it's weird they list possible causes as a faulty sensor and nothing else.

I'm sure someone more helpful will chime in, but otherwise check wiring. Which, verifying power and ground and all that stuff should be done before replacing components anyways

[getslideways]

also make sure that the sensor is being plugged into the correct plug. If they are flip flopped the ECU will be telling you the wrong physical location.

[V1nny]

my rears are coded out and yes, its passenger side. Will go and look at the wiring and connector one more time.

[Mille Bornes]

also make sure that the sensor is being plugged into the correct plug. If they are flip flopped the ECU will be telling you the wrong physical location.

Hadn't considered that although I just came across a TSB telling techs to mark which plug is which if they're disconnected lol

[MacDaddy]

I had a land rover that would throw o2 codes unless it had bosch sensors (didnt like NTK or universal) it also used bosch motronic ECU, so its worth noting.

Maybe swap L&R sensors and see if the problem goes to the other bank, if so check continuity from ecu plug to sensor plug.

- - - Updated - - -

*meant to say "if not"

[V1nny]

Rear O2 sensor wire was touching downpipe and had insulation melted. It did not cause any codes, because my rears are coded out, but it shorted the ECU bus enough to cause intermittent code on the upstream sensor. Only code left now is 17965 - Charge Pressure Control P1557 - 35-00 - Positive Deviation

[audi-hammer]

Hmmm interesting I'll have to check that out