P2096 Code 5k miles after replaced O2 Sensor

[timcorle]

I have a 2002 996 and last summer had the P2096 code pop up, my mechanic replaced the O2 sensor. I put about 5K miles on the car. I had the car in storage for the winter, from November until just a week ago. I took the car out, drove it about 50 miles and the CEL came on again, and the code is P2096. I have to get it into the shop for an oil change and inspection, but I wanted an education on what might be going on. I don't think I should have to pay to have it replaced again since it hasn't even been a year since it was done. Any insights on this would be appreciated. The car has 37K miles on it now.

Thanks

[JFP in PA]

Which sensor was replaced as the code is specific to a sensor location.

[timcorle]

The service record says they ran aging test and replaced bank 1 sensor 2

[JFP in PA]

That is the correct sensor; Bank 1 is cylinders 1 to 3. Which is on the left side 996.

The code is the sensor after the cat (muffler side).

As the sensor is new, it should not be showing signs of aging, which is what the code is for. I would ask the following: Who's sensor is it (aftermarket or OEM)? Does it have a plug on it like the OEM sensor would, or is it "hardwired"? I would also suggest unplugging the sensor and cleaning the plug ends (if they are still there) with contact cleaner, reconnecting the sensor and clearing the code to see if comes back.

In addition, I would get the car scanned (Durametric software is fine)to get a record of how the O2 sensors before and after the cat are responding, you may have an early indication of TWC cat failure. A good TWC would scan entirely different than a one that is failing:

[timcorle]

Thanks I will ask those questions and clean the sensor. Hopefully I am not looking at TWC failure, it would seem to me that it would be way to early for that kind of repair on a car with less than 40K on it.

[JFP in PA]

Thanks I will ask those questions and clean the sensor. Hopefully I am not looking at TWC failure, it would seem to me that it would be way to early for that kind of repair on a car with less than 40K on it.

Not really, these cars have cats that are susceptible to vibration and often die early on cars with a lot of track time on them or hard use. A comparison scan of the before an after sensors will show the cat's condition.

[wvicary]

Use a high quality contact cleaner that is silicone free.

[Silver_TT]

First, I would clear the code and see if it comes back.

In the mean time I would clean the electronic contacts as wvicary suggests. I have a recent post on this site which shows the location that the sensors plug into the DME, they are very easy to get to (drivers side is sitting right out, and passenger side only requires removing the air filter housing which is very easy).

The information JFP attached showing how to interpret the o2 sensor readings will give you a very good indication if your cats are bad.

For more information, you should read my recent post on this. It's quite lengthy but will give you a lot of education on the issues you're looking at.

Edited March 25, 2013 by ferrugia