I didn’t see anything here in Rennlist or elsewhere online that shows how to expose/access the coolant expansion tank so that I can inspect the tank and fittings for a possible leak.

Can someone help me out?

TIA.

Perfect, that did the trick.

I didn’t see any sign of a leak associated with the expansion tank, but where it drips on the undercarriage and then on the ground is right below the reservoir. So I haven’t completely ruled it out yet, since the conditions today aren’t when the slow drip occurs anyway.

This intermittent ‘drip’ I’ve mentioned previously only occurs in unusually cold temps and when the vehicle has been sitting unused (daytime high in the 20s or below). Other than that (like now that it’s back in the 40s), no problem. I describe it here in this thread I posted last month... https://rennlist.com/forums/cayenne-...-2011-ctt.html

I’ll just have the dealer look at it again (they checked it early last year for the same thing and found nothing, even with a pressure test). I’ll have them check it at the time I bring it in for the AH08 recall.

Thanks again, much appreciated.

Very interesting to hear that! Yes, sounds like what I’ve been experiencing. Same place, same conditions.

Also interesting to hear you’ve already had the thermostat housing replaced and it still occurs. I was thinking that might be the cause based on other stuff I’ve read, but perhaps not? I’m thinking along the lines of something (a loose hose fitting maybe) that contracts/shrinks enough when really cold to allow a slow drip to escape? It’s still a mystery, and I noticed it on mine over a year ago, and as I mentioned before the dealer checked it once already.

Other than the specific conditions mentioned, it’s fine the other 99% of the time. Weird!

I see. So that further tells me that it probably isn’t the thermostat housing causing this mysterious cold weather minor leak since yours does it even after having the new thermostat housing installed.

I’ll certainly provide updates if something comes to light. Please do the same as well.

Now that the mid-Atlantic region where I live is out of the extreme deep freeze we had been in for quite a while, and temps are more seasonal for this time of year, it’s dry as a bone. No drips whatsoever, as is typically the case. The mystery of the ‘deep freeze drip’ continues.

Hmm, that would make sense...if one of the o-rings was compromised a bit, extreme cold could shrink things enough to start a slow drip. Definitely a possibility. Thanks.