Cat and 02 sensors question/story

[87bertone]

Greetings -

Re a '98 328is with 150k miles - After several months and a few thousand miles of resetting various CEL lights and I bought a new DEC cat from Bimmerparts.com and 4 new 02 sensors from Bav auto and had them professionally installed by well known MA BMW specialty shop, good guys, fair price for labor IMHO.

Here's the part I don't understand. About 200 miles after the install a table 11, code 37 CEL came on, it's for a pre-cat O2 sensor heater (cyl 4-6). (this is a CEL code I've never seen in the old faulty cat days)

I've crawled under the car, checked all the wiring, and to the best of my knowledge everything looks OK. My question to the group relates to the possibility of a defective O2 sensor. Is there such a thing for a new O2 sensor to give up the ghost after 200 miles?

I was considering whether to manually remove the pre-cat O2 sensors and literally swith them, i.e install the 1-3 sensor in the place of the 4-6 sensor and see if the same code pops up for the other bank. Can a new o2 sensor go bad so fast? Any thoughts? Thank you

[HyphE36]

I would definitely switch the sensors and see if it pulls the code in the other grouping.

That is really weird if it faulted under 200 miles... maybe you just ended up anti-lucking out and got a bunk sensor...

[stang_me1990]

switch them for sure. very well could have got a junk sensor, bulk electrical components always have that chance....bad part bout the electrical components is that parts store will not return them or stand behind them usually.

good luck and hope its as simple as one new sensor

[HyphE36]

Yeah, I hate buying electrical parts for that reason... I spent 50 dollars at the dealership on relays to try and fix my lighting issues, did it all right there in the parking lot, didn't fix anything, so I went back in (no more than 5 minutes after buying and tried to return them (I also wiped off the dirt they gathered on their quick trip into my power distribution box) but was told they could not take back electrical parts, even if they weren't used... once you pay for it, its yours...

I wasn't too thrilled ><

[drivinfaster]

the heated circuit could be a poor connection in the socket, a break in the winding of the sensor, or in the circuit itself. swapping the sensors is a very good idea. if the fault moves, then voila, you have your answer. if the fault remains, then it's time to track down the culprit. hopefully though it will just be the sensor.

df

[87bertone]

To make the day even more perfect the AC blower suddenly stopped without warning, however all displays are working fine, etc. I suspect the FSU. Boy do I hope these electrical gremlins are part of a inter-car conspiracy.....Dooh.

[HyphE36]

Oh they are....

Its all a plot to take over the world i tell you...

The Nazi's didn't lose the war, they just had to relocate.... to our BMW's in the form of electrical gremlins! bankrupting countries whose citizens love great german engineering, pun intended...