I'm reposting my question since the thread I posted in got off track about whether the car can smell bacon or not. While amusing, I need a real answer

--- Original question below ---

My auto recirculation used to work fine. But after about 6 months, I started noticing the smell of diesel exhaust behind trucks or buses. My dealer replaced some sensor, but it didn't help. When I took it in and complained again, they ran some tests and claimed that the sensor is working fine. They stated that:

"The AUC sensor that controls the auto recirc function does not detect diesel exhaust. AUC sensor is operating properly at this time."

In other words, they say that I should expect to smell diesel fumes because the sensor isn't designed to specifically detect it. I find this hard to believe. Anyone out there have solid evidence that I can use to dispute their claim?

 

Sorry for hijacking your thread when you had a serious issue. Unfortunately I have no hard evidence but clearly the manual states that the auto function will respond to "unpleasant odors or pollutants". I would classify diesel fumes as one of those and mine has always done a good job of shutting them out. I would suggest you start getting BMWNA involved and documenting your communications with them because clearly your service dept is not doing its job. Something is not functioning correctly on the car. Maybe the sensor is working fine, but failing to shut off the outside air. Is there another dealer in your area you can try? Anyway, good luck and sorry I wasn't more helpful.

 

Mine has done an excellent job of keeping out fumes of that nature. I'd push your dealer a bit more.

james

 

Same here, I never notice diesel, or other smells when the auto circ is on. I've been quite pleased with it's performance. Push the dealer harder......they're slacking!!

 

it could be the re-circ flap thats not closing properly... I would think they've checked that... but thought I'll throw that out to make sure.