[moze26]

Hello, I am hoping someone can help me shed some light on this situation.

I have my check engine light on now, so I took it in to BMW for a check up. The following is word for word of what was written on the report:

176 scanned car had all heater activation faults on O2 sensors ckts not working. Ver lines and all O2 sensors ok. Gnd ok. Found supply not present on activation lines. Found short on heat activation lines. Found short on crankshaft breather element.

I asked the mechanic for clarification and he said that the element that heats up the O2 sensors was faulty and needs replacement. He referred to it as the crankshaft breather element. They wanted to charger me 1100$ for this, about 160$ parts and 5-7 hours of labor. This part is supposedly located on the engine block. If it isn't supplying the heat for the O2 sensors, they will eventually fail and this can lead to worse problems.

The problem is that I was under the impression that the O2 sensors had the heater element inside them and not an external one. I tried searching for this crankshaft breather element and not much comes up. I am lost and not sure how to proceed with his.

Does anyone have and idea of what this can be or advice?

My car is a 2007 323i with just about 87,800 kms, so just about 55 000 miles.

Thanks!

[bumere90]

never heard of such thing
do you have the list of part numbers by any chance?

[BMW_Belgier]

Good luck!!!

[moze26]

Aziz,

He did not have the list part number, when I asked him for it he said he threw it out since I refused the service. Sounds very fishy.

I just took it in to a local BMW mechanic and showed him the diagnostic and even him he was unclear of what the problem is. I am starting to feel that he was trying to scam me somehow. Even the search on the net brings up barely anything.

I am just concerned because my check engine light is on. Apart from that my car is running great!

Any other ideas?

[moze26]

I just got off the phone with the BMW Service Manager. Himself he couldn't understand the diagnostic. After further investigation it was determined that the problem is the intake manifold heater that has a short on the circuit with provides the heating to the O2 sensors. I was told this can wait considering it is summer and the sensors should be hot enough, however it needs to be treated before it gets cold out.

Did anyone ever have a similar problem ?

[Brandontyler42]

I've had the most frustrating time trying to diagnose a similar issue with my 2006 E90 325i!

She keeps throwing codes for all four of the O2 sensor heaters (p0031, p0037, p0051, p0057), and I dug into the A8680 fuse carrier to see, lo and behold, the 30A fuse was popped. I replaced the fuse, cleared the codes, and immediately the SES came on again. So I dug a second time, and sure enough, the fuse was popped.

Long story short, I eventually unplugged each O2 sensor separately and rechecked the fuse each time, thinking that one of the heaters was shorting the circuit. Unfortunately, even with all four unplugged at the same time, the fuse popped every time. So now, 2 weeks, 6 fuses, and many dirty-Bentley-manual-pages later, I've narrowed it down to the possibility that the crankshaft heater (which is also shared on the same fuse), could be shorting the fuse. But there's nothing online about that!

UNTIL I found this thread: so far your issue is the most like my situation that I've seen as of yet. What happened with yours? Did you get it settled? Please update me! I'd like to figure it out before I dismantle the whole intake manifold :/

Thank you!!