Hi guys

06 CTTS threw a CEL today, I just checked it, and got a P2629. I searched here and Renntech, can't really find much information. O2 sensor? Which one? Is that a big job?

Google shows this:
P2629 O2 Sensor Pumping Current Trim Circ/Open Bank2 Sensor 1

Is the car safe to drive? I need to drive 400 miles Monday, and was planning on taking the pig.

Thanks
pf

 

There are four lambda (02) sensors in total, two per bank. One sensor is mounted before the catalytic converter and the other downstream. P2629 CEL denotes a failure of either the sensor or wiring associated with sensor no.1 (before the cat) on bank 2 (R.H. or passenger side).

After many miles and on/off cycles, the sensor becomes one with the exhaust pipe port in which it is mounted. Some come off easily with some penetrating fluid and a bit of effort, while others may require a torch. On the Turbo, the front wheel, inner fender liner, engine cover cowling and air cleaner box must be removed to access the sensor. In addition and in most cases with the Turbo, the exhaust manifold may have to be loosened from the engine in order allow clearance for dismounting the sensor; although some techs have claimed success w/o having to do this. You'll also require a special open-end spanner to unscrew and re-thread the sensor.

If all of the above sounds like a foreign language to you, I would leave this job to a qualified technician.

 

Thanks Andy

As far as a foreign language, somewhere in between. I've had the front wheel, wheel lining, engine cover and air box out before. I have never done it before, but from what I read, changing an O2 sensor doesn't sound worse than a spark plug - depending on where it's located. And if it is fused to the pipe, I may be in over my head, but at that point, I can button everything up and go the my Indy.

I'll pop that open tomorrow, and check the wiring too. If I can get it out, I can put a new one in. However, that will take some time waiting on the part. Is it safe to drive in the meantime? I was planning on driving to the coast on Monday. With the family - next largest car is a Fiat 500 - they've nixed the 996 and 944.

 

I reset the code with my icarsoft POR-II, didn't come back. I'll take a short trip today and see what happens. I'm around 150K miles, would it be a good idea to replace all O2 sensors? I don't know if they have ever been done.

Took some readings after the car was warmed up
Ox. Sensor (LSU) voltage ahead of cat. C. 1 1.5 V
Ox. Sensor (LSU) voltage ahead of cat. C. 2 1.7 V
O2 sensor downstream, bank 1 0.7 V
O2 sensor downstream, bank 2 0.8 V

There are some other readings, not sure if relevant, I was looking to see if bank 1 more or less matched bank 2, and they did.

enginecodes.com had this information
Possible causes:
Faulty Heated Oxygen Sensor (HO2S)
Heated Oxygen Sensor (HO2S) harness is open or shorted
Heated Oxygen Sensor (HO2S) circuit poor electrical connection

P2629 Description:
During Deceleration Fuel Shut-Off (DFSO) the Powertrain Control Module (PCM) monitors the integrity of the Universal Heated Oxygen Sensor (HO2S) UO2SPCT circuit by comparing the actual oxygen sensor voltage signal to an expected oxygen sensor voltage signal. The test fails when the actual oxygen sensor voltage exceeds the maximum expected voltage threshold for a specified amount of time.

Read more at: http://www.engine-codes.com/p2629.html

 

At 150k miles, the O2 sensors owe you nothing. Normal life of them is typically spec'd to be 100k miles.

You may want to check aftermarket. Porsche doesn't make sensors, and the basic designs are pretty standardized. I'm sure some company offers functional equivalents. I imagine the Porsche price is silly high..

 

Follow-up:
All O2 sensors replaced, CEL is gone (knock on wood!)