Hello all:

I am new to the forum.

I would appreciate if someone could instruct me on where my o2 sesnor is located, and how to subsequently replace it. Thanks to all in advance.

 

have u read the code, it should tell you which sensor. u can search this forum and find LOTs of info...

 

Hello:

I Just returned from a MB dealer diagnostic with the following error results:

1. Hi voltage for rear O2 sensor

Code PO138- Circuit High Voltage and Switchover valve controls
Recieved "Mixture too rich" fault.

2. Upshift delay- My car shifts aggressively in 1st and 2nd gear, moreso
when cold. Dealer indicated that is may be Throttle actuator, whatever the hell that is....

I was informed that the O2 sensor needs replacing...