Probably missing. Could be a prior battery change made it disappear.

 

 

I remember reading about this in the news a long time ago. It's been bugging me since as I couldn't remember hooking up a vent...kinda like "did I forget to unplug the curling iron before leaving this morning"

After reading this follow up, I sent myself a reminder this morning to check it out when I got home from work.

Yes, I did hook up the vent tube.
And for those singing the praises of AGM batteries...THEY NEED TO BE VENTED! If the charging system fails, you won't be any less dead than if you had a lead acid battery.
Each side of the AGM will have a vent hole and one will be plugged. If the vent tube is on the other side, swap the plug to the other side and plug in the vent tube.

 

My Napa Gold AGM in my Cayenne has the vent hole, which i hooked up, but none of the Optimas I have in any of my other cars or my boat have a vent hole or anywhere to hook up a vent line.

 

Those are NOT meant to be installed within the cabin of a vehicle.
https://www.optimabatteries.com/en-u...-fitment-guide
Specifically:
Trunk/interior mounting – If your battery is mounted inside the passenger compartment or trunk (common in many European makes), the battery must be vented to the outside of the vehicle. OPTIMA group 27, 51, DS46B24R, 78, 34C and 31 batteries all have ports for connecting a vent hose.

 

Good to know. Guess the only ones I've ever bought were not those listed. The boat uses a 34M and the 997s a 34R. Looks like the only group 34 that has to be vented is the 34C. In all my other vehicles, the battery is in the engine compartment so doesn't matter, and the boat even though not a 34C also has plenty of fresh air circulating.

 

As with many weird tragedies like this one, a bunch of rare/weird things had to ALL go wrong at the same time:
0. a car with the battery in the passenger compartment
1. battery probably not installed with the vent properly connected
2. some charging problem probably caused an over-voltage, causing the battery to emit a ton of gas
3. insufficient ventilation to fresh air - windows up, cabin air recirculating
4. driver ignored the smell until too late.

Any one of those done differently would have probably saved them. It must have been a really strong odor based on the reports of the first responders approaching the car and smelling it.

Yes, I have newfound respect for the battery vent tube. In addition to the Cayenne of course, my X5 has an internal battery (in the trunk, which is still inside). And my old VW Vanagon (sold :-( ) had one under the front passenger seat. Prior to this, I had always assumed the vent was to get corrosive vapors out, preventing damage to the car. I never would have thought it could kill you like this.

And oh yeah, this reminds me - for those with Cayennes with the second battery in the back - that one counts too. It's inside, just like the one on my X5.

 

True about battery wrongly installed without connecting the vent but Advance and AutoZone don't do these. I bought a 2006 Titanium model with tow package (SCAM) in early july this year. Battery started having problems in August and I had to charge every few days. In September I looked up batteries and bought one from Advance and was told the company doesn't do extensive battery replacements. Testing my old battery showed I had a 600 CCA battery and it was borderline fried. Both here and another Porsche forum state the ventilation system needs to be specifically checked when changing. My guesstimate is reading she had only just bought her Cayenne a few months prior to her death so previous owner or his shop changed the battery and failed to properly connect the ventilation system. Sad news story but it needs to be seen by more because some things like this need more dedicated attention to detail to properly complete not just a 10 minute swapout like on a 1988 clunker under the hood.
Now to explain why I said SCAM about my towing package. Well what good is an incomplete package? All it has is a hitch receiver and no harness. According to Porsche to install the harness requires PCM programming as well to "accept" or "recognize" the load when it is used and it is not cheap. Why offer 50% of a package to only charge lots more to complete and be able to use it? I thought the 2006 Titanium model was "special" in it's own right not just decorations.

 

You do realize you are talking about a company that will "not" put things in a car to make it a "special" edition and then charge you more for it right? The answer is the same as always...they can. Most buyers, certainly new buyers, are so enthralled with the new they often are either under researched or overwhelmed with the "experience" and these kinds of things slip by them.

Marketing...it's a hell of a drug.

 

My Cayennes have all had the towing package and they have all come with the factory harness. Maybe someone added yours after the fact? Run the VIN and see if the Towing package is listed in the options.

 

mine is the one year off Cayenne S Titanium edition. I read somewhere the tow package was standard on these. It is the factory hitch. I never had the owners manual to look over so maybe I am missing something? Earlier link I saw was dead for the pdf manual. I enjoy the Cayenne very much just the bump in the road for hitch wiring. I did inspect upon purchase the upgraded cooling pipes and cardan shaft so both of those worries taken care of. Sold a 2004 Boxster to get this one. Both red so when driving I still get the feeling of the Boxster just sunroof instead of convertible.

 

My 955 was also the lipstick on a pig model (lets get these things off the production line Hans.. the new ones right behind it..) aka Titanium /S.

No hitch. Never had it. It wasn't standard. ALL that was "standard" on the Ti model was the GTS body cladding along the sills, the special paint colors (lifted right from the VW paint supplies), and the two-tone interior. They didn't even give anyone a dash plaque - but they did emboss the door-sills as Titanium.. that's "special"... oh - and maybe the two tone rims, which I actually did think looked pretty cool..