Jump to content

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

I'm confused by a fault that keeps appearing on my 2011 Cayenne S.  71,800 miles, I've owned since 70,500 with little history known before my ownership. Therefore sorting through the usual new-owner issues. 

 

I'll illustrate with an example. 

- Last night, car was running perfectly, had been fine for about 150 miles - connected Durametric and saw no codes under engine, PSM, tiptronic, AWD etc 

- this morning - 60 mile roundtrip - about 3 miles from home suddenly car feels like it's running rough, maybe on 6 or 7 cylinders, dashboard alternates between "Check Engine", "PSM Failure" and "Start-stop deactivated"

- switched car off/on - no change

- got home and read codes as follows:

  Engine:   P0305  Upper limit value exceeded

  PSM:   U112300   Databus error value received Factory Fault Code 336397    Warning Indicator On   Test Completed This Monitoring Cycle
       Test Not Failed Since Last Clear  Test Completed Since Last Clear  Not Pending DTC  Test Not Failed This Operation Cycle   Fault Active

  AWD:  293 / 125  PSM activation by PTM  Warning Indicator Off  Pending DTC   Test Failed This Operation Cycle   Fault Active

  AWD:  12656773 / C12085  Check PSM control unit fault memory content   Warning Indicator Off  Test Completed This Monitoring Cycle  Test Failed Since Last Clear
       Test Completed Since Last Clear   Pending DTC   Test Failed This Operation Cycle   Fault Active

 

 

So the P0305 is misfire on cylinder 5, I get that.  Back home the car was idling and running roughly when I cleared that code and it instantly smoothed out.   Does it shut down cyl5 when a misfire is detected more than some number of times?  Normally I'd pull that plug and inspect/replace that coil etc, but the fact that it happens in conjunction with all the PSM warnings has me suspicious. 

 

Can anyone throw some light on the PSM and AWD faults?  Searching for those numbers hasn't helped yet - still searching, but thought I'd ask here too. 

 

Note, clearing these codes cleans everything up, no codes return and all runs perfectly - until next time (3 cycles so far)

 

-Richard

Santa Cruz, CA

2011 Porsche Cayenne S

 

 

  • Like 1
Link to comment
Share on other sites

  • Admin

:welcomeani:

 

When I see random seemingly unrelated intermittent electronic faults on a Cayenne the first two things I think of are battery and grounds.

These cars are really susceptible to a weak battery or corrosion on the main ground cables. I would check those first.

  • Like 1
Link to comment
Share on other sites

  • 4 weeks later...

My 2011 Turbo has 80k now and the triple fault started a year and 10k miles ago, when it was still under CPO warranty. I guess the dealer service departments are incentivized to do the most expensive fix, so when i took it in, they replaced the coils on misfiring cylinders. Now that the warranty is expired, i sure hope you are right on the battery issue since it's acting up again.

Link to comment
Share on other sites

2 hours ago, swpender said:

My 2011 Turbo has 80k now and the triple fault started a year and 10k miles ago, when it was still under CPO warranty. I guess the dealer service departments are incentivized to do the most expensive fix, so when i took it in, they replaced the coils on misfiring cylinders. Now that the warranty is expired, i sure hope you are right on the battery issue since it's acting up again.

Hello, and thanks for the reply.   

On another forum suggested the bad-coil idea - and there was one code which suggested a misfire on cylinder 5 - that cylinder was therefore shutting down and the car running rough until I cleared the code.  I changed that single coil, and the car hasn't had the problem since - therefore I changed the other 7 coils. 

It seems that changing coils should be a service item - everyone who's had the problem sees them failing at about 70k miles like mine. 

 

Thanks, 

 

-Richard

  • Like 1
Link to comment
Share on other sites

  • 3 weeks later...

I changed out all of mine as well. When I dropped my '11 Turbo off at my garage, the service manager said that were going to send a camera into the cylinders after pulling the plugs. My explanation of the fault codes he told me the camera is to check for scoring. He's told 2 other '11 turbo owners in the last month that they need an engine replacement. Porsche isn't helping out either. I was quite happy to hear that my cylinders were unscored.

Link to comment
Share on other sites

  • 2 weeks later...

I just had this happen to my 2011 CS w/95,800 miles yesterday on the way home. My first thought, when I started seeing all the warnings pop up, was the variocam bolts let go. Fortunately it smoothed back out after I pulled off. I read/cleared the codes with my Durametric when I got home and all was fine on the way into work this morning.

 

Based on the research I'm betting on it being a coil starting to go bad. The local dealer wants twice as much as mail order so I'm hoping things will last until a replacement coil gets here in a few days.

Link to comment
Share on other sites

1 hour ago, Tom M said:

Based on the research I'm betting on it being a coil starting to go bad. The local dealer wants twice as much as mail order so I'm hoping things will last until a replacement coil gets here in a few days.

 

Yes I bought all 8 from Sunset Porsche.  The problem has never re-occurred. Good luck, 

 

-Richard

Link to comment
Share on other sites

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.."

Link to comment
Share on other sites

  • 1 month later...
On ‎8‎/‎5‎/‎2017 at 4:23 PM, doublegarage said:

I'm confused by a fault that keeps appearing on my 2011 Cayenne S.  71,800 miles, I've owned since 70,500 with little history known before my ownership. Therefore sorting through the usual new-owner issues. 

 

I'll illustrate with an example. 

- Last night, car was running perfectly, had been fine for about 150 miles - connected Durametric and saw no codes under engine, PSM, tiptronic, AWD etc 

- this morning - 60 mile roundtrip - about 3 miles from home suddenly car feels like it's running rough, maybe on 6 or 7 cylinders, dashboard alternates between "Check Engine", "PSM Failure" and "Start-stop deactivated"

- switched car off/on - no change

- got home and read codes as follows:

  Engine:   P0305  Upper limit value exceeded

  PSM:   U112300   Databus error value received Factory Fault Code 336397    Warning Indicator On   Test Completed This Monitoring Cycle
       Test Not Failed Since Last Clear  Test Completed Since Last Clear  Not Pending DTC  Test Not Failed This Operation Cycle   Fault Active

  AWD:  293 / 125  PSM activation by PTM  Warning Indicator Off  Pending DTC   Test Failed This Operation Cycle   Fault Active

  AWD:  12656773 / C12085  Check PSM control unit fault memory content   Warning Indicator Off  Test Completed This Monitoring Cycle  Test Failed Since Last Clear
       Test Completed Since Last Clear   Pending DTC   Test Failed This Operation Cycle   Fault Active

 

 

So the P0305 is misfire on cylinder 5, I get that.  Back home the car was idling and running roughly when I cleared that code and it instantly smoothed out.   Does it shut down cyl5 when a misfire is detected more than some number of times?  Normally I'd pull that plug and inspect/replace that coil etc, but the fact that it happens in conjunction with all the PSM warnings has me suspicious. 

 

Can anyone throw some light on the PSM and AWD faults?  Searching for those numbers hasn't helped yet - still searching, but thought I'd ask here too. 

 

Note, clearing these codes cleans everything up, no codes return and all runs perfectly - until next time (3 cycles so far)

 

-Richard

Santa Cruz, CA

2011 Porsche Cayenne S

 

 

 

Richard,

 

   I recently had the exact same concern on my wifes 2011 Cayenne S with 63k on it.       Cylinder 8 misfire (P0308)  and would come up with PSM failure, auto stop disabled, abs, 4wd system, etcetera.    

 

   I found the spark plugs were original, and I had 4 cracked ignition coils.   I replaced all spark plugs and the 4 cracked coils.    This resolved both concerns.         My suspicion is that RFI from the cracked coils is likely occurring, which can interfere with any Hrtz or Voltage signal from other sensors, and can simply ***** off multiple modules.  

 

    I see this in the dealership all the time on other makes of vehicles (been a Ford senior master tech for 20 years now).   Its generally hard to diagnose, but typically leads to ignition or charging system issues causing the RFI interference .     Since you are throwing a misfire code (as was I), it is most likely that is the cause.   I would repair the condition, clear all codes and recheck.          

 

 My wife and I have since put on another 4000 miles with no issues.   We are also replacing the remaining 4 coils as a precautionary measure.     Replacing the plugs and coils is a very quick and easy task, with the only special tool needed is an inverted torx socket.    The whole job should not take much more than an hour.

 

Link to comment
Share on other sites

  • 2 months later...

Join the conversation

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

Guest
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.