[Bimmer_nerd]

Hello Fellow F87 Enthusiasts,

Is anyone running into oxygen sensor issues with their M2C? My car has 30k miles now and has had the oxygen sensor fail twice po0036 (bank 1 sensor 2) and po0056 once. When both sensors failed at 25k miles I had both replaced at the same time with bmw genuine o2 sensors thinking that they were damaged during the DP install. 5k later I'm now experiencing another failure this time just one sensor but its probably a matter of time before the other sensor fails as well. Looking for advice on how to avoid buying more o2 sensors.

Current mod list:
NGK 2 step colder Spark Plug
VRSF charge pipe
MAD catless DP non resonated
AA single non resonated mid pipe
Remus Race Catback
Bootmod3 flex fuel sensor
Bootmod3 stage 2 flexfuel antilag multimap tune
Mostly on 91 and occasionally mixing in e85

Thanks for your input!

[mecheng77]

I know silicone can damage the O2 sensors.

Have you tried cleaning them instead?

[Bimmer_nerd]

Originally Posted by mecheng77

I know silicone can damage the O2 sensors.

Have you tried cleaning them instead?

The last set was verified bad by a BMW performance shop SVBimmer, and they recommended that they were just replaced. I will look into cleaning them this time around and see if that does the trick

Thanks!

[Bimmer_nerd]

Shop confirmed the O2 sensor was not providing the right resistance and recommended another replacement. No solution as to why it keeps breaking

[F87source]

Originally Posted by Bimmer_nerd

Shop confirmed the O2 sensor was not providing the right resistance and recommended another replacement. No solution as to why it keeps breaking

Do you use octane booster or non-o2 sensor safe race gas?

Do you use anti-sieze on your o2 sensor?

[Bimmer_nerd]

No race gas, just ACN91 and occasionally e85

I believe anti seize is used when they installed the sensor, I'll have my shop verify and get back with the confirmation.

Thanks!

[F87source]

Originally Posted by Bimmer_nerd

No race gas, just ACN91 and occasionally e85

I believe anti seize is used when they installed the sensor, I'll have my shop verify and get back with the confirmation.

Thanks!

If you use antisieze you gotta make sure it doesn't get onto the sensor or else it will foul and kill it.

[Bimmer_nerd]

Confirmed with the shop that any aftermarket antiseize was not used. Wasn't sure whether or not antiseize was used in the last 2 that broke however since the parts were thrown away before I asked. They dropped in the current sensor as is coming from bmw (there might be a little bit of antiseize out of the box.

Thanks!

[RockCrusher]

Originally Posted by Bimmer_nerd

Confirmed with the shop that any aftermarket antiseize was not used. Wasn't sure whether or not antiseize was used in the last 2 that broke however since the parts were thrown away before I asked. They dropped in the current sensor as is coming from bmw (there might be a little bit of antiseize out of the box.

Thanks!

When I bought factory O2 sensor for my Porsche cars the sensor threads had some light grease on them but it was *not* anti-seize.

One must not touch the sensor tip and do not clean it nor spray any contact cleaner on the sensor or wiring harness connector. Some sensors "breathe" via their wiring lead and any cleaner in this can foul the sensor.