Pre cat o2's

[opihi5]

Originally Posted by eatsleepboost

What about us that have superchargers and are not running through o2 sensors? We are making way more power than a tunes m3. The power and heat are not related. I over doubled the power on my last car with Bosch sensors and the manifold would glow red it got so hot and the front o2 sensor 8 inches away lasted years.

Op what fuel are you running? Any chance you have put leaded fuel through the car or e85?

Edit.. just saw you are getting heater codes. That has nothing to do with the flow of exhaust across the sensor. That is simply a heater that warms the sensor up to operating temperature.

The car is currently on e85 but all the problems were consistent before the switch. If my codes arent related to the flow how would i go about fixing it. Cant find much on the heater sensor. Ive never had one fo put before the other so it might be a fuse? Not sure what else it would be

[dparm]

Originally Posted by opihi5

The car is currently on e85 but all the problems were consistent before the switch. If my codes arent related to the flow how would i go about fixing it. Cant find much on the heater sensor. Ive never had one fo put before the other so it might be a fuse? Not sure what else it would be

The heater circuit is an extra wire on the connector that warms the sensor up on cold starts. Do you have access to the BMW service manual/ISTA? It would have a diagnostic process for that code.

If not, take the car to the dealer and let them handle it.

[kabeero]

anyone else still having problems with these Bosch sensors? I just had another precat sensor go bad, lasted two months / 2200 miles

[P1zzaboy]

Still have the issue. The code disappears on track days and come back on the way home from the track..

[Bakerboy]

I'm pretty confident that you are experiencing these problems because you have an exhaust leak at the donut joint where it meets the manifold.

I had the same issue and had to try twice to get it to seal properly. used a smear of sealant with new gaskets in the end.

I would throw same codes as you quote. The exhaust gas is leaking and air getting in throwing it outside of the limits of what the o2 is capable off hence the codes.

Mine is code free now. one way to tell is get someone to rev it with your hand close round the join when its not too hot, you should feel the blow if it is.

[M3talllic]

My personal experience... I had this same issue and I also have the Gintani bubble tune. I never had an issue prior the tune. I was tired of going through sets of o2s so I tried out some extension space adapters and voila! Over 10k miles later and not one issue.

[Bakerboy]

Originally Posted by M3talllic

My personal experience... I had this same issue and I also have the Gintani bubble tune. I never had an issue prior the tune. I was tired of going through sets of o2s so I tried out some extension space adapters and voila! Over 10k miles later and not one issue.

Is that wise with the precats as its a wide band for measuring the gases and making adjustments.

I can understand post cat o2 as they just check the cat working

[M3talllic]

Originally Posted by Bakerboy

Is that wise with the precats as its a wide band for measuring the gases and making adjustments.

I can understand post cat o2 as they just check the cat working

It may not be the "best" solution but it was something that was recommended by Gintani since I went through 2 sets. By my third set I had it and was not going to do this again. So, I tried it out and it has not given me a single issue since then

[Dave07997S]

Originally Posted by Bakerboy

I'm pretty confident that you are experiencing these problems because you have an exhaust leak at the donut joint where it meets the manifold.

I had the same issue and had to try twice to get it to seal properly. used a smear of sealant with new gaskets in the end.

I would throw same codes as you quote. The exhaust gas is leaking and air getting in throwing it outside of the limits of what the o2 is capable off hence the codes.

Mine is code free now. one way to tell is get someone to rev it with your hand close round the join when its not too hot, you should feel the blow if it is.

I said the same thing.

[Bakerboy]

Any updates on your issues OP?

[MPower7]

Originally Posted by dparm

The heater circuit is an extra wire on the connector that warms the sensor up on cold starts. Do you have access to the BMW service manual/ISTA? It would have a diagnostic process for that code.

If not, take the car to the dealer and let them handle it.

Would you be able to explain this problem further? I'm having the following problems.

2741 Lambda probe heating controller diagnosis before Kat Bank 2
274F Lambda probe error Nernstleitung before Kat Bank 2

Codes P3027 and P2247. Looks like it is the Bank 2 Sensor 1. Going to replace this. Should I do both Pre Cat Sensors or just he one throwing the code?

[MikeYQM]

Originally Posted by M3talllic

My personal experience... I had this same issue and I also have the Gintani bubble tune. I never had an issue prior the tune. I was tired of going through sets of o2s so I tried out some extension space adapters and voila! Over 10k miles later and not one issue.

Are you still running spacers on your pre cat O2? Any adverse effects? I’ve replaced my Pre Cat O2 twice in 2020 and just got a code P2629 again today.

Thanks