Nate.Evans

2012 CS. Did a search, and this sort of mimics my problem:

https://rennlist.com/forums/cayenne-...both-side.html

How mine is different is I noticed my left front was sagging about 10mm ONLY when in normal setting...it would do all the modes and would be level in every other mode, but if I selected normal height, for whatever reason it would lower the front passenger side 10mm lower than all the other corners. Hooked it up to PIWIS, did a check, all systems were fine so I reset and remeasured and re-input values for the ride height settings, cycled through all the suspension heights and now it's level as it should be. BUT, after I park, and lock the doors the rear suspension lowers to the low setting. At first I thought it was a leak, but I checked everything. No bubbles. The compressor doesn't have any weird random pumps like it would on a leaking system. So I parked it in front of our securty camera and it automatically lowers to low setting ONLY in the rear. Sometimes 1 hour, sometimes the next day, but you could clearly see it on camera lower it to the setting, not leak/lower over time. I can leave it for a week and it never gets any lower once it reaches that height.

Sticky/leaking valve? Is there a PIWIS setting I missed where it automatically lowers the suspension when parked? It never lowered the rear before me resetting the height values to level it out, but now it does making me think there's a default setting I may have missed or something....

Otherwise, system works and operates as it should!

Daveheardt

I don't have air suspension on mine but I have some weird recent PIWIS experience that could be helpful to you.

I tried disabling the Auto Start/Stop system on my car via PIWIS and allegedly everything went smoothly. Did a rescan with tests and no issues whatsoever were detected. However, when I took the car for a drive on the next day I found out that my Auto Start/Stop system is still working in the same fashion and my wheel heating was enabled all the time. Immediately went back, connected PIWIS and reverted the Auto Start/Stop function to "always on" (as it was) - now the function still operates the same but the heating is not enabled all the time.

Don't know what it is, perhaps some mismatch between the PIWIS version's codes and the car's computer codes but that seems to be a glitch and it's scaring me to attempt anything else with my PIWIS 3 on my 2011 CD. If you are using PIWIS 3 on your 2012 - it could be something similar enabling some "factory default" setting you didn't even try to apply.

Nate.Evans

Ya know, that was happening to me as well. I noticed I would have to input things sometimes twice for it to “take.” For example, when setting the suspension heights, sometimes it would only change 2 or 3 of the 4 wheel values. I’d have to run the system check again, then input the value again just for the wheel that didn’t take and then it would take. There was no rhyme or reason as to why it wouldn’t take but simply running the procedure again would rectify it.

I’ll take a look again and see if there’s any factory setting it somehow enabled/disabled. Any ideas on what to look for? As far as I know there is no “parking mode.”

Daveheardt

Since I don't have air suspension (and I am inexperienced with PIWIS) I can't look for any air suspension settings on my car. I asked one of my neighbors (owns a Macan) and according to him various Porsches with air suspension have auto lowering tech, which usually activates at speeds higher than a certain limit, or when parked. Apparently his car has been doing the same thing you are describing since day 1 and he considers it "a feature". But then, his car goes all the way down on both sides - front and rear. I don't know whether his car is suffering from the same problem (but on both ends) or whether your car has the same feature (but only one end).

Getting the "level" on front/back or driver/passenger screwed up by PIWIS - that seems to be a common complaint. Quick Google search reveals different cases when people complain about this and even dealerships being unable to fix it. Perhaps that has something to do with the lower levels the car goes to? Like, it should go all down to a certain setting on all sides but because of "screwed up data" (or whatever it is) it only gets applied to one side?

One thing is for sure though, by doing factory resets you might've told your car to start doing things it has previously declined to do (for whatever reason). That happened to mine with my rear left door - it wasn't unlocking from the key fob until I factory reset the immobiliser and now its getting unlocked every time.

By all accounts, from what I gather, it doesn't seem like there's any reason to worry about a mechanical problem. Sounds more like a software feature/glitch. That said, and given mine and yours PIWIS experience - it might be worth trying to rewrite the heights values few more times until all systems "comply"?

Just to be on the safe side here - I am not an expert, don't take my word for it. I am just giving you food for thought and I am sharing any knowledge I have/I can get my hands on

Nate.Evans

I fine tooth combed PIWIS and couldn’t find anything about a parking setting or sleep setting. Google gave no help either.

It’s odd because I can work a 10 hour day and it not sag at all (I’ve actually measured the height when I park going into work and then measured it when I got off). But I can come home, be home for a few hours, come outside and it be all the way lowered with the rear wheels almost tucked into the fenderwell and the fronts not change a mm Unlock the doors and as soon as I open the drivers door, it inflates the rear to the proper height.

It’s the most perplexing thing. I made an appointment with a local indy on Wednesday who seems to think it’s a leaky compressor seal as if it were the shocks it would be astronomically crazy for both to happen at the same time and have the same rate of leak…which is a reasonable assumption.

garrett376

You can easily diagnose this yourself: when you park at home, turn off the Level Control with the console switch before leaving the car. Does it drop after a few hours? If it does, you have a leak. If it does not drop, it's not a leak and something with the control systems permitting it to drop.

Nate.Evans

I did that already, it’s lowered in the morning and the level control is active again when I come out to start the car. That was the first thing I did. I just assumed level control the-enables after awhile to prevent people from accidentally driving with it off. I’ll try it again.

garrett376

How did you disable level control the first time and how did you know it was disabled?

Level control will ONLY reactivate if you drive off, re-enable it with a tester, or re-do the disable routine by holding the console switch for over 10 seconds. It will not come back on by itself just sitting there.

Nate.Evans

hold the lever for 10s and the notification pops up on the dash saying suspension is disabled. It’s was definitely disabled.

I brought it to another shop and they did find the leak, both rear air bags are leaking at the top. As for why it lowers on its own, they don’t know for sure why, but they did observe it happen too while it was there. They’re making an assumption the system sensed a pressure differential and then lowered it to a position with less psi, I.e. the lowered mode to protect the system. There is no other explanation that they can think of.

Dcdoc

I'm having the same issue. I´ll also be checking the rear suspension for leaks.

I found a thread of another person having the issue and in his case was due to corrosion of the top o-rings close to the mounting position. Link: https://www.clubtouareg.com/threads/...please.284645/