ATF smell coming from vents

[911nick]

I'm completely baffled by this one for my 2006 Cayenne S. About two weeks ago I did the whole transmission fluid change service myself including the filter, gaskets, fluid, etc. All went well, and the transmission operates as it should. However, upon start up, and after the truck has sat for a long duration, I get a very brief but distinct whiff of ATF coming through the fresh air vents. It comes and goes within seconds, and that's it. A couple of days ago, I lifted the vehicle and took a look at the tranny plugs, pan, and hard lines. All is dry. The only other thing I can think of is fluid possibly escaping from somewhere in the engine bay area. I don't know much about the mechanism there and how the smell could get into the fresh air intake. Any ideas?

Edited August 3, 2014 by 911nick

[jagman1]

ATF and also gear oil have a very strong and pungent smell to them as you know.  I wouldn't be surprised if it's just residual on the outside of the car that's wafting into the air intake.  That or you had some on your hands and it made its way into the passenger compartment.  Either way, if all is dry underneath, then I think you're good to go and the smell should subside with time.  

[911nick]

_{Thanks jagman 1. Very true about the pungent smell of gear oil, especially Red Line D4, which is what I used. However, it is still very strange to me that I only smell it right after I start the truck, and it's through the fresh air vents for only a second.}

[911nick]

I did a little experimentation and turned on just the ignition without firing up the engine. There is no tranny fluid smell without the engine running. So, when the engine is running, the transmission is under pressure. This leads me to rule out the possibility of risidual ATF that may have spilled somewhere while I was servicing the transmission. I have serviced manual and automatic transmissions before, but never have I smelled gear oil afterward. Of course, this was my first time servicing a sealed tiptronic. So, now I'm thinking that I may have overfilled. If this is the case, does the Cayenne S transmission have an overfill valve or a breather hose?