04fivefour

Pulled code 41 KOER self test, description says no 02 sensor switching, code was in memory, anyone with experience with this code have any input, seems very straightforward, replace 02 sensor or look for open/short in wiring?

Joel5.0

If the O2's are old and have some mileage on them, replacing both is a good alternative. Also make sure the passenger side header doesn't have any exhaust leaks causing the lean readings at that sensor. You could also switch O2 sensors from sides, rerun the KOER, and if code 91 shows afterward, it will confirm that sensor is at fault. LUK

AdderMk2

did you run th test while the engine was at full operating temperature???

04fivefour

yes, right after a long freeway drive, i'll try swappin side to side