deilenberger

I guess you'll find out when you install it if that fixes your problems. I've yet to hear of one doing this - so let us know how it works out. And the unplugged transfer case test is one the dealerships apparently use to determine if the transfer-case is at fault. I wouldn't drive it any real distance that way - but around a parking lot, it's unlikely to hurt anything.

Ashish - I suspect Porsche put 850ml in, expecting you to use 850ml. I wouldn't be overly concerned about spilling 10-20ml. The oil is circulated through the transfer case by both the action of the chain running through the bottom of the case (below the fill port) and what appears to be some sort of pump flooding the clutch area (which is up high in the case.) It will continue to do this even missing 20ml. The only real effect the missing 20ml might have is to cause the case to run a few degrees warmer than if it has 850ml in it.

Sloop, What did they do for $230 as far as "service"? Just curious. The list price for the Porsche fluid is around $50 or so (widely available for $40-45), and it takes about 10 minutes tops to change it. They may have replaced the fill and drain plugs - which would add about $30 in parts to the bill. Seems the charge is excessive - but I guess getting out of a Porsche service department for less than $300 has to be considered a bargain.. (I did get out for less than $200 a week or so ago when I had my brake fluid flushed. That did seem an OK charge since it took 2 techs to do it - and it took them about 45 minutes..)

I'd be very interested if you can install the modified breather tube. As far as I can see - the breather is on the very top of the transfer case, and only really accessible with the case removed. And the piping for the vent going up into the engine compartment - it also appears to need the transfer case removed to install. Let us know if changing the fluid helps the performance issue.

It's possible the transfer drive motor has crapped out - but surprising - it's not a common failure on the 958 series. More common is the entire transfer case - that will give the symptoms you describe as "hesitant and jerky". One test for the motor is to unplug it (it will give a warning message) and try driving a short distance. If unplugging it clears up the bad behavior - then chances are that the transfer case is on it's way out. I'm surprised you could find a 4 year old turbo with no miles on it. Is there a back story to this? One thing worth checking when oddball electrical problems start occurring - is the condition of the battery. That's particularly suspect if the car sat unused for 4 years - and still has the original battery in it. You can opt to display a voltmeter function on the multi-instrument-display in the dashboard - be worth seeing what the engine off voltage is. Ideally 12.7V engine off.. and it shouldn't drop below 10V when the engine is cranking. The other possibility is corroded wiring in the front footwells. ALL Cayennes are prone to having drains plug up due to debris that falls on the vehicle and then is washed down into the drains. There are several cowl drains that are accessible by pulling back the inner fender liners. It is not at all uncommon for these to become plugged up, causing flooding inside the vehicle - under the carpeting. The fix is to clean them out - and most people remove the rubber drain that sits in them, allowing debris to pass through in the future. Then once they're cleaned out - the carpeting has to be pulled up, and the corroded connections found and fixed. Not a trivial job. There are threads on the drain issue on rennlist.com - and there may be some here. I know there are threads on repairing the wiring on rennlist. Good luck!

I would agree with Loren on using the latest Porsche fluid. It has recently dropped in price in the US - down to about $45 / 850cc - which is one oil change. The alternatives aren't a lot cheaper. The issue that Ashish may have experienced might have been caused by the difference in rolling diameter when the tire was under-inflated. The smaller diameter would cause that wheel to turn more revolutions per mile than the other wheels on the car. The transfer case only balances out front to back torque balance - but if one tire is badly underinflated - it's possible it caused extra stress on the case clutch. As Loren suggested - fix the tire/wheel issue - then change the oil and see what the results are. Let us know how it works out for you.

Just check the threads on the transfer case woes. I'd suggest also visiting rennlist.com - and check the 958 Cayenne subforum. There is an extensive sticky thread there.

Tom, you may want to read up on the actual thermostat housing: https://rennlist.com/forums/cayenne-958-2011/1045931-2011-2014-serious-issue-coolant-pipe-glue.html I would certainly consider at least JB_Weld'ing those pipes in place while you have it apart and accessible.. if not replacing the housing.

While anything is possible with enough money - in this case - the money spent to do this would seem excessive to me. Problem is - as with almost all German cars - if an option wasn't spec'd when the vehicle is built - the wiring for it simply isn't there. And it's not simple to add the wiring since it's usually part of another harness, which may wander throughout the vehicle. The factory system (from memory) has 4 antennas - one for each wheel, located behind the wheel well liners. There is likely a control unit also. Adding this much equipment, then creating a custom wiring harness to make it all work, and enabling the function in the Gateway/ECU - would likely run into the several thousands of dollars range. There are systems made for aftermarket installation. They typically use a small display, requiring 12V power/ground, and 4 RF equipped wheel sensors. Cost is more in the $100-200 range for these. Problem is - where to put the display where it would be visible but not intrusive. I'd have to sit in mine to come up with an answer for that.. This propensity of the Germans to never add an unused wire is probably ecologically sound practice, and even engineering sound practice - but it does make retrofitting anything to a vehicle a really expensive chore if you want to go with OE equipment.

A recall is for an issue with the potential to cause injury or death to the driver, passengers or surrounding people. Manufacturers look at recalls as a black eye. If they get serious ones like the Chevy ignition switch, you know there will be people lining up with personal injury attorneys waiting for their chance to sue Porsche for real, or imagined injuries. A recall is a last resource for a manufacturer. Some manufacturers - when faced with a potential recall will setup a "service campaign" where they fix the problem when a vehicle arrives in their shop. That's generally done at their expense (usually billing back part or all of the cost to the OE manufacturer who supplied them with the failing component, if they didn't build it themselves.) Toyota/Lexus love to do this - it's why my wife's Lexus gets dealer oil changes - there is almost always some issue that is addressed for free while the car is there getting the oil changed. NHTSA is where "recalls" in the USA come from. They have a website. There are forms on the website for reporting issues that have caused injury/death, or you feel have the potential to cause injury or death. If enough people make identical complaints about an issue - the issue will usually percolate up to the actual human employees of NHTSA who are in charge of investigating the reports. An example of this process working would be the "Camshaft-Controller-Recall" (Porsche's name for it.. I'd call it a Variocam recall..) In threads discussing this problem on several forums, instructions were given on how the reporting process works - and how to most effectively report an issue (several things have to be identical in order to build up the "mass" of reports that will trigger an investigation.) People did report the issue to NHTSA (not just complain on the forum) - and there were some very credible reports of close calls for serious injury since the failure could result in a vehicle with no brakes, power steering barreling down a freeway. The mass of reports was enough to catch the eye of a defect investigator, who then reached out to a few people asking for additional information. The information supplied to them was copies of recalls that Porsche had issued in other countries for the identical problem. At that point Porsche was notified of the investigation, and apparently felt it might be best to be pro-active in it - and they voluntarily issued a recall. Whew... so that's what has to be done if you expect a recall to happen. Some manufacturers avoid recalls by offering buyers an extended warranty on the part in question (BMW loves this - they've given out 100k engine guarantees on multiple engines any number of times - to avoid a recall.) The highest number I've seen on these extended warranties is typically 100k miles. BMW-Motorad (motorcycle side) has an extended warranty in place for 12 years, unlimited miles for a fuel gauge sender that regularly fails - and people run out of fuel on their motorcycle in risky conditions. That was done in response to a similar campaign that was coordinated on a BMW motorcycle club forum I'm a moderator/member of. NHTSA expressed interest in it (other manufacturers, both bike and car - have had recalls for similar failures.) BMW extended the warranty. So far - I've had about 10-11 of the fuel senders fail and replaced at no cost to me. I'd be much happier if they'd simply solve the problem though. So one other thing - a recall is only really a solution IF the manufacturer has devised a way to solve the problem. In the case of the transfer case - it's not clear that they have. This went on a bit longer than I thought it might when I started it. If it gives anyone ideas - I'd be happy to discuss the NHTSA process off-line with you. DISCLAIMER: I have nothing to do with NHTSA. The above ramblings may well be the spurious thoughts of a madman - or not. Use at your own risk. YMMV. LSMFT. I did stay in a Holiday Inn Express this past week though.

It's amazing to me that Porsche basically tells you to never change the driveline fluids.. with active clutches in the transfer case and the torque-vectoring rear diff - its certain that the fluid will deteriorate - due to sheering from the clutch, and material worn from the clutch. WHAT are they thinking?

I had the clogged drain - and it was cleared and still is. I've added cleaning it out to the schedule for replacing the cabin filter. That may have been about when this behavior started.. my iCarScan shows the outside/recirc flap is a bit slow to perform.. it does reach the desired position - but it fails the test for doing so (which apparently is position and time based.) My thinking was that perhaps this flap or the motor got wet and are binding up a bit, so I figured the biggest hole into the HVAC housing is the motor opening.. plus it would give me a chance to lubricate the motor bearings. If the flap was binding up (and the sound from the HVAC system sounds as if it's switching from inside to outside air) a bit - the control module may make it repeat the function until it gets it right, which could account for the repeated airflow decreases on startup.

The footwell floods are quite common. They don't come up to the level of the battery compartment. There is about 1.5" of open-cell molded foam under the front carpet. Under that foam are big bundles of wires going hither and tither - that have splices in them. The foam gets soaked, meaning the bundles of wire are basically underwater, and the water creeps past the rather poorly sealed splices, and combined with electricity - cause electrolysis - basically converting the splices into a form of copper-dioxide. Which isn't a good thing. When they go wonky - there are all sorts of odd behavior that's been observed - especially if one of the bad splices happens to be in a computer data line. I'll see if I can find a thread to read about it.. it is an ALL Cayenne sort of thing. None of them are immune to it - from the first 955 up to the last 958. See: https://rennlist.com/forums/porsche-cayenne-forum/1002135-if-you-re-thinking-of-buying-a-955-957-2003-2010-read-this-first.html Specifically the section entitled: 955 & 957 - Cabin Floor Flooding: Also see: https://rennlist.com/forums/porsche-cayenne-forum/987845-help-my-floorboards-are-flooded.html https://rennlist.com/forums/porsche-cayenne-forum/960439-how-to-ignition-lock-brake-proportioning-abs-light-psm-traction-brake-flashing.html Almost everything described in these threads (on the 955/957) applies equally to the 958. Makes a good case for parking it in the garage..

Interesting. Can the motor regulator be replaced individually? I have a persistent error on the HVAC module, related to excess current draw by the HVAC fan. I can clear it and it reoccurs. The fan works fine - once it's started. It does start oddly. It starts at high RPM (and high RPM indicated on the LCD display) - then I hear flappers moving around, and the air velocity drops drastically for a second. Fan speed according to the display has not changed. After the second - the air-velocity increases again. It then may (or may not) repeat this cycle once again. From then on it runs normally. I tried to drop the blower motor to see if I could determine what was going on - but it foiled me on removal. The big-*** (tech-term) bundle of wires that pass beneath it made it almost impossible to get all the screws out that hold it in, and when they were removed I could only drop it about 1/2". Since it was getting late, and I was getting sore from standing on my head in the vehicle - I put it back together. Any hints on either? Regulator available as a part? Getting the **** thing out? TIA.

Hi Richard, Well, I haven't been to Santa Cruz since June (by motorcycle..) if you wanted to drive to NJ - we could hook it up to my iCarScan and see what happens. The symptoms you're giving make me think the alarm system is reporting something unlocked - and letting you know with the funny door LED flash and the 4 way flashers. That's where a good diagnostics tool can be a lot of help - it can check each sensor and see what the body module thinks the state of it is. I'm going out to the garage to try something.. Back, lets see if I can remember what I saw: Normal operation - all doors closed, gas door closed - hit lock on the key, the LED on the door flickers, two chirps, then the LED flashes rapidly for 20 blinks (about 1/sec between blinks) then it switches into a slower blink mode (maybe 2-2.5/sec between blinks.) All doors closed - gas door open - same as the normal operation. It seemingly ignore the gas door.1 A passenger door partly latched - LED comes on solid for about 10 seconds, followed by pairs of blinks - about 1/2 second between the two in the pair, and about 2 seconds between each pair. So blink-blink, 2 seconds, blink-blink. No parking light flash, and no chirp. Drivers side door partly latched - it simply doesn't lock at all. What I didn't try is keeping the latch on the gas door from fully extending to the lock position - and my WAG is - that might be your problem. Since it doesn't care if the gas door is open or closed - it isn't monitoring the gas door position, but it might be monitoring the latch state of the solenoid that latches/locks the door closed. Just checked the manual - the rear body-control module is located "RIGHT SIDE OF REAR COMP" - but it has several outputs to the "TRUNK, TAILGATE, FUEL DOORS SYSTEM". Looking at the diagram for that circuit - the FRONT BODY CONTROL MODULE actually controls the ACTUATOR TANK COVER OPEN and ACTUATOR TANK COVER CLOSE outputs - which are interesting since there are just these two leads going to the TANK COVER ACTUATOR - no ground shown. That makes me think they reverse the voltage going to the actuator to have it open and close. The FRONT BODY CONTROL MODULE is located "LEFT SIDE OF DASH". The reason I'm zeroing in on filler latch assembly is - you hear noise in that area. There is nothing there that should be making noise. The rear body module has no relays that would click - it's solid-state switches - they make no noise. Something in that area is making noise, and the only thing I can think would do that is the filler latch assembly. It's located under the rubber and plastic surround around the gas filler and appears accessible without major disassembly. It may require that the hinge-assembly and surround be replaced if it's removed from the car. The manual isn't entirely clear on that. I just went and took a look at how it works. It's a spring loaded piston that rotates 1/4 turn between in and out. It engages and locks itself to the actual gas filler door as it retracts. When fully retracted some sort of catch keeps it that way, holding the gas filler door closed. When you open it - that catch releases, it pushes the gas door open about 1/2" and releases itself from the door. The lock on it must be when it's locked it doesn't release from the catch that keeps it retracted. Typical German complexity for what should be a simple device.. You might leave the door open and see how it works by pushing it with the locks unlocked, and then again with the car locked. If it's making the noise you hear - you might have found the problem. One other scary thought - has your vehicle ever suffered from the flooded footwell syndrome that all Cayennes are prone to? Given how the wiring for that device must run from that corner of the vehicle to the diagonal opposite front corner - chances are the wiring runs in the bundles that can be damaged if the footwells flood for any period of time. They're fixable - and could account for the problems the Durametric is having with communications. HTH, Don

BTW - is the gas door locked when this happens? Just wondering if a failure to lock the gas door throws a failure warning that the vehicle lets you know about by dancing around with the routine you've described.

Suggestion - find someone local with a competent Porsche diagnostics tool and find out what the codes are that Durametric won't read. I'd suggest iCarScan - but I'm biased - I like it a LOT more than my Durametric and find it much more competent and complete.

My suggestion is - if one coil is on it's way out - all it's little sisters and brothers are just waiting for you to replace the one and then they'll start failing. Makes sense - the coils die because of heat - and too much current pushed through too small a coil (causing some of the heat) - and they live in identical conditions. When one goes - replace all of them. Throw a few of the old ready-to-fail ones in the spare tire well to invoke Eilenberger's Law of Spares: "You'll never need the part you have.."

Thanks much for the kind words. What were the symptoms you were experiencing and year/model/miles?

Loren - dunno if you notice - this thread is in the wrong section. FWIW - there are some rather lengthy threads on various Cayenne forum websites describing this fault on the 955/957 series - and some fixes. The problem is wear within the column control devices (magnets on shafts that move in/out of hall-effect sensors) - a few people have bodged a fix for it that doesn't require steering column replacement (Porsche's solution.) I have also heard of this happening if the wiring bundle under the passenger's or drivers floor carpeting has gotten water soaked and the splices within it corroding. This usually also causes other fault codes.

Nowhere in the ebay listings I looked at did it refer to China. Some of them referred to Turkish made parts (which is likely exactly where the originals were made.) Did you actually see a reference to China in any of the listings, or was that simply an assumption based on the price? My WAG - someone at the company making the switches for VW/Audi/Porsche liberated some and is using eBay to market them. I can't imagine there is a big enough market for these very custom switches (different options and years result in different switch configurations) to be manufacturered simply as a replacement part - even in China. And the fact that parts of the switches are being sold (the buttons - which frequently loose the chrome tip) reinforces that WAG. YMMV..

If the fill tube wasn't removable via the drain plug you couldn't drain the oil except by removing the pan.

The probe on the digital thermometer - if inserted in the fill tube will be measuring the temperature of the air in the transmission.. unless you insert it while fluid is pouring out of the fill tube (seems rather messy.) I think plan B has more chance of success. And the temperature isn't critical to 1-degree.. nor is the level IMHO. Porsche owners do tend to obsess sometimes (I'm not innocent of this myself..)

Even better - the switch caps are available - considering how frequently they break.. good thing: http://r.ebay.com/zId2iZ and these replacements are made in Turkey (which is probably where the original switch was made..)

Dougg - interesting the iCarScan will do it fine with the 958. I think Durametric is really falling behind the curve on value and the diagnostics ability. At one time it was the only thing out there - no so anymore - and other options give more value for the money.