Jump to content

The RennTech.org community is Member supported!  Please consider an ANNUAL donation to help keep this site operating.
Click here to Donate

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Recommended Posts

Hi all. 


New to the forum, on the Cayenne end of things anyways, owned a few 80's and 90's turbos before, now its family time, bought a 2004 Cayenne S for my new family (having my first baby soon) 


Well.. Got a great deal... spending a lot to chase some dragons. 


So, I dont really know these cars in specific, but i know cars enough to not be too scared to get a used one. This particular car had no history, test drove it and it was great. Only major issue i could see was the factory nav deck wouldnt turn on, Low range mode selector/diff lock switch wasnt lit up or working and there were some noises like servos in the dash. Easy fix i thought from what i read. 


Anyways. Now i've had it for a week and i've decided to bring maintenance up to check, so i had the oil changed, put spark plugs (ngk iridium), coils(beru), air filters, cabin filter and bought O2 sensors and a transmission filter / gasket kit to get that done soon.


So, problems i've noticed which prompted a bunch of the maintenance was :


1) Bad gas mileage, like bad bad... Dash says i can get down to 11.4 l/100km but my wallet says different. Half tank of premium and im at 250 km...


(i have a sneaky feeling that since i looked into the reason why the diff lock selector wasnt working i messed something up. Selector switch was disconnected by the previous owner. Possibly there is a fault in the system and is now engaging something that is killing my gas mileage, even tho there are no lights telling me its on or in any mode, I do hear something in rear engaging after starting the car.)


2) Key fob doesnt work all the time. Always locks but the red blinking lights dont stay blinking for very long and then when i get back to the car to unlock, the key button keeps re locking the car. After a ton of tries, unlocks. Sometimes the clock is reset as well after going into a store. Back gate button doesnt work and neither do the kessy buttons on the doors. Also linked to the locking/unlocking/resetting issue was lights and rad fan. The lights would start to dim and then get bright while i had doors open and rad fan would blow after stopping the car when it was hot, slow down slightly then get back up to speed, up and down up and down. 

To me: a battery or not enough charge situation. 


(today i replaced the battery under the seat, I have both, rear hatch and seat batteries The one under the seat was totally flat, yet had been installed in jan 14 according to its sticker. Once the battery was replaced the key fob worked like a charm, not the door buttons, but lock and unlock from the key button was great. Also Lights light up bright and hold brightness and the rad fan stays at a constant speed but stays on for a very long time.. not sure if thats normal) 


This caused a new issue: I noticed when the car was off, the wipers would just barely enable, im talking like a minor engaging sound and barely visible twitch out of the wiper arms, every 20-50 seconds. Now after 4 hours, key is back to crappy and locks suck, all the power issues again... HELP???


3) Under the dash the temperature controllers are messed up, I hear that you can get some servos and replace them your self. Any one know what parts i'd need for that? My local parts place doesnt have a part number for them and i dont want to go to porsche. Basically when the car has power/key engaged, theres the sound of a CD player trying to find a track ... CONSTANTLY!! its annoying. and the temp isnt regulated properly cause of it. 


4) The fan for the inside ac and heat system for some reason doesnt start for about 1 minute after starting the car. Always. just turns on after 1 min and then works fine at whatever speed i put it at. but will never start immediately with the car. Tho today randomly started with the car once...  I dont get it. 


I've seearched online for DAYS now and cant find a straight answer to the issues. Battery draining thing is bugging me badly. 


Thanks guys! 






Link to comment
Share on other sites

  • 1 month later...

Hi, I'm new to this group also but have been reading a lot of answers and tech stuff and it certainly seems like a lot of knowledgable people in the midst .anyway you have a lot of issues going on here and one of my assumptions is you have a major electrical fault somewhere leading to a lot of those problems .i also have a feeling someone has a few things unplugged to try and hide a few lights coming as you mentioned about the transfer case. First thing,you have to load test the electrical system completely .Cranking and running lights off and fully loaded ..that's a start ....results will give you a clue as to what's going on there and may be related to a lot of the issues..good luck for now ..

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.