pesuazo

Got this code while driving last week...based on internet research found to be one of the after cat O2 sensors.

Since they have not been changed (originals) I decided to change both: BOSCH13723 for 154.33 total (with shipping and tax)

The O2 on the passenger side came out easily with a 22mm wrench, plenty of space for leverage working under the car, and "broke free" relatively easy.

The driver side...that is a different story....use a 22mm O2 sensor socket....get a 3/8 18"-24" extension and a breaker bar...working from the top...hope this tip helps someone.

If you try from underneath, you may strip it (mine was starting to when I first tried).

Whomever tightened the driver side at the factory used gorilla strength...I had to pull hard on that breaker bar just to "break it free"....rest was done by hand.

Note: Both O2 sensors did not look bad when removed, however, given that they were original from factory I decided to change the "good one" as well

islaTurbine

I recently replaced all four of mine. The two on the drivers side were definitely a pain so I ended up spending 5-10 minutes to remove the rear bumper, beam and heat shield to gain more access. Doing this also allowed me to get a torque wrench on all four sensors.

Optionman1

My indy also recommended doing all 4 recently after getting CEL code

pesuazo

What codes did you get before replacing?

Optionman1

P2096
Porsche Fault code 16 - Oxygen sensor ageing Delay bank 1

Part 996.618.660.15

Optionman1

Mechanic's philosophy was all the sensors probably went in at the same time (18 years ago) so might as well replace all when the first begins to show signs of a problem. Seemed reasonable advice to me so we did. BTW my car is a 996.2 (03 4s) so the codes may very well be different than on a 99 model.