Questions you thought were too dumb to ask E53 edition

[ProfessorX5]

My question... will you damage your car driving with P0128 and P0155 codes going on?

[tmv]

ProfessorX5,
P0128: Tstat stuck open. Your engine run cold, rich and never reach normal operating temp. MPG goes down. No short term damage to engine, but you would want to take care of this since there would be more wear on a cold running engine.
P0155: O2 sensor heat circuit bank 2. Did you replace them yet? I suspect they are original.

[ProfessorX5]

No, didn't replace them yet. P0155 had showed up when I scanned it at the dealer, and he said he'd take care of it, and it didn't show up again until now, 2000km later.

Would a cool running engine cause this? Also, how do I tell which 02 sensor it is?

I also read on another forum that an intake leak can cause a P0155, but not sure if that even makes sense.

[hunds02]

Does anyone know the part number of the metal locking ring that secures the sensor wire to the MAF? I lost this a while ago and I want to make sure the cable is securely attached.

Thank you

[ProfessorX5]

www.realoem.com might have the answer.

[hunds02]

Yes and I have checked and could not find it. Can anyone please help out?

[ProfessorX5]

What should I expect to pay to have an indy to the CCV for me?

[Ricky Bobby]

Parts are about 160 or so, I'd figure they'd quote you probably 3-4 hours labor, not sure what book time is on the job. Probably looking at 500 in labor, you provide parts. that's just my guess.

[ProfessorX5]

Wow, 3-4 hours? That BavAuto guy made it look so easy :P Ah well.

[tmv]

Originally Posted by ProfessorX5

No, didn't replace them yet. P0155 had showed up when I scanned it at the dealer, and he said he'd take care of it, and it didn't show up again until now, 2000km later.

Would a cool running engine cause this?<-see answer below Also, how do I tell which 02 sensor it is? <-pre-cat O2 sensor, bank 2 is cyl 4-6, closer to the firewall.

I also read on another forum that an intake leak can cause a P0155, but not sure if that even makes sense.

OBD Code P0155
This code refers to the front (translate: pre-cat) oxygen sensor on Bank 2. The heated circuit in the oxygen sensor decreases time needed to enter closed loop. As the O2 heater reaches operating temperature, the oxygen sensor responds by switching according to oxygen content of the exhaust surrounding it. The ECM tracks how long it takes for the oxygen sensor to begin switching. It the ECM determines (based on coolant temp) that too much time elapsed before the oxygen sensor began operating properly, it will set P0155. <-Your question is answered right here.

Symptoms
Possible sumptoms of OBD code P0155
You will likely notice poor fuel economy the illumination of the MIL.

Causes
Possible causes of OBD code P0155
A code P0155 may mean that one or more of the following has happened: O2 Heater element resistance is high. Internal short or open in the heater element. O2 heater circuit wiring high resistance open or short to ground in the wiring harness.

Possible Solutions
Repair short or open or high resistance in wiring harness or harness connectors Replace oxygen sensor (cannot repair open or short that occurs internally to sensor)