need help identifying trouble code for my z3 3.0i

[BMtroubleyou]

Hello again everyone. So I was driving my z3 the other day and when I hopped in and turned it on the service engine soon light popped on. I went to my local firestone where I formally worked and plugged it into the OBD2 scanner and discovered a few trouble codes. I unfortunantly don't understand them and was hoping someone out there may be able to point me in the right direction of what's broken and needs replacing.

-lambda control limit bank 1 & 2 too lean

-lambda conroller deviation bank 1 & 2 too lean

-Functional check Tev.

Now i'm assuming because it says bank 1 and 2 that it may have something to do with the catalytic converters, however I could be wrong.

I appreciate any constructive feedback I can get. This is my daily driver since the 2002 needs a 5 speed tranny rebuild and tabs.

Thank you for your time.

(O=00=O)

[ifayeoh]

i would not think the cat just yet. if this is a high mileage car i would start with a Fuel treatment like Techron or something like that. I am pretty sure this code is related to the O2 sensor which is probably getting old. Has your MPH dropped since new? Clear the code and see how long before it comes back. If comes back within 2 weeks, O2 sensor.

i think bav auto has a how to on replacing this.

have fun

[BMtroubleyou]

i would not think the cat just yet. if this is a high mileage car i would start with a Fuel treatment like Techron or something like that. I am pretty sure this code is related to the O2 sensor which is probably getting old. Has your MPH dropped since new? Clear the code and see how long before it comes back. If comes back within 2 weeks, O2 sensor.

i think bav auto has a how to on replacing this.

have fun

Do you mean MPH or MPG? my miles per gallon has dropped a few numbers. the z3 has about 80K miles on it now. I did reset the codes once before and it was a couple of weeks ago. I was doing that just to see when it would come back and how long it would take.

Now I can start with the 02 sensors and fuel additive again. I've been putting fuel additive in about twice a year.

my hope now is that 02 sensors are not seized in the pipes, from how hot they could of possibly gotten over the years and how much corrosion could be on them.