I changed my primary o2 sensor recently because i was lead to believe it had been fouled because of a major oil leak on my turbo. (im not turbo'ed at the moment). i was getting some very rich arf's after about a month of driving without my turbo on

i changed my o2 sensor, reset the ecu, and let it "relearn". its been about 500 miles since i did the change and im still running extremely lean at idle. like around 16.2. has anyone else had this problem? also i live in chicago and its extremely cold here, could the denser air cause my car to run that lean?
anyone in the chicagoland area run that lean at idle??

 

16.2 at idle is fine there is no load on the engine. It will bounce around at idle. If you are underload and running that AFR then you should worry. Have you cleaned your MAF and changed your spark plugs? Just to try and see what it does?

 

16s is nothing to worry about with not under a load... i know that on my friends 06 he got a 15.8 afr when cruising and idle .... and ive seen the 08 tc doing 15.3 idle and cruise


alot of things can come into play with ur afr like.... whetere theres a leak before the sensor..

but yea i wouldnt worry... floor the car... if u see 13.0-13.3 your golden

 

at wot im at 13.2 most of the time. good to hear, thanks borderguy