2012 Panamera S
Really odd thing has happened twice now. Going wide open throttle (to the mat) the car immediately pings 3 different warning lights:
- Chassis System Fault
- Electronic Parking Brake Fault
- PSM Failure

Shut the car off and turn it back on and they're gone. I repeated the error today and immediately drove it home and plugged in my POR2 without shutting the car down. As soon as the unit accessed the electronics, the warnings all went away. Dug into the modules and one error remained - it was for the level sensor. Cleared it and it has not returned.

I was thinking it may be something shifting and causing a short, but that would probably manifest itself in a non-clearable error. Tried driving it around in a parking lot and wagging the car (hard) side to side to see if that would make it happen, but it does not.

Any ideas? Maybe coils? I've heard of bad coils causing PSM failures.. car has a new battery, too.

Edit: Just went out and beat the car like a rented mule to get the errors to pop up. No dice.

 

Do you mind sharing the error code? (If there was one).

 

That's the thing, once I plugged the POR2 into the car to read the codes, they all went away. I even ran the 'self test' on the unit and the car came back with no codes. So nothing was even stored.

 

I hate when that happens. There's a code, it clears, then doesn't return.

At least you can still run her hard. Eventually I
became traumatized with so many issues that I drive like I'm sitting on eggshells.

There's those strange cube shaped clips on top of the air struts. I noticed even the guys at the highly reputable Indy don't always connect them properly. Maybe start by checking them:

 

Since you were doing WOT, I assume you were doing it in Sport + mode. Even if in sport mode, behavior is similar when it comes to errors.
If in sport or sport + modes, PASM, level, height, etc, are all monitored. Any of them throws one code, the entire mode is turned off and car goes to normal mode. This results in subsequent errors sometimes, which seem as separate errors themselves, but are really a consequence of one initial error which turned off the mode.

- Chassis System Fault - the level system experienced some non critical fault recorded by ECU. This could be any number of things, but can only be certain by reading with PIWIS or good scan tool. These faults are volatile, they will disappear from ecu ram once I think car is turned off.

- Electronic Parking Brake Fault - this may be unrelated, and may have to do with the way parking brake pads were set if you at some point were replacing rotors and pads. Rear wheels have parking brake adjustments and pads, I believe, and if these are not adjusted periodically, you can get faulty brake errors. Or if the connection to the pads becomes faulty in some way. IMO that is a separate item to look into.

- PSM Failure - this one could be couple things, one being a redundant error, which was thrown because you unexpectedly exited one of the sport modes. Another, could be due to some other issue related to car accelerating, such as spark plugs or coils, anything that can affect WOT performance really, including traction control. This is best to be scanned for error details. Many generic scan tools only give you brief description.


After you do your diags, clear out all errors, so you know what comes back. Find out exactly what the chassis error is, reconnect electrical connections at shocks (if you messed with them recently, be gentle), wonder if your shocks are losing air, as height difference can be detected and throw a code. Another is behavior of the valve block (if some valves stay on too long, or too short). Just some ideas, but those have to be diagnosed with tool. Hope this helps some.

 

Thanks for the replies. Car was not in sport or sport +. Just normal. Car doesn't show any errors or stored codes. Hooked it up and looked at live-data from all of the systems. Everything appears to be functioning within spec. Parking brake works fine without error. I thought it may be a misfire causing the PSM code, so I got it good and warm and went out and did some more WOT runs trying to get it to fail while live-logging misfire data. Car performed flawlessly and no errors or misfires were recorded. I am starting to wonder if it IS in fact a coil or two going bad. Car has 59k on it and they're the original coils. I've read over on the 911 forums that bad coils have caused PSM errors along with a whole host of different phantom errors.

This may just be one of those "drive it until it fails" sorts of electronic gremlins that can only be caught when it completely poops the bed.

 

Coils will sure give different errors. I think their replace time is about 40k (I have a maintenance intervals doc on here to verify).

 

How's your tire pressures? correct tire sizes? Might not be relevant but who knows, could contribute to PSM and the Chassis System.

 

Update: popped the error twice yesterday and was able to have the reader connected during one of them. This time it also popped an ABS error. I was able to catch a "front right speed sensor implausible" flag. Turned the car off, errors went away and the sensor read correctly. Live logged it while driving and the sensors (all 4) looked to read ok, but I've seen sensors come and go before they outright fail entirely. Thinking about the other errors, it makes sense that a bad speed sensor would cause the other systems to freak out.

More diagnosis later today. I'll continue updating.

 

I had the same thing happen, it was bad coil(s). Replaced the coils and plugs, all fine now.

 

Live-logged the car while on a drive today. The error popped up and this was the data I caught:


The log is about 2 frames per second, so going from 6 mph to 0 and then jumping to 8 mph within 2 seconds is probably a good indicator of where the problem is.

 

Ordered the sensor ($300+ - wtf...) and a new set of Beru coils, just in-case.

 

Installed the coils yesterday. Holy %$*&Q( - what a difference. The car is so much smoother when at speed. Wish I'd have done that sooner. The ABS sensor code still pops, but the engine is happier. Waiting on the part from Porsche...

 

Glad to hear your car is getting better! Looking forward to reading it going back to tip top shape. I noticed the plugs on the non-turbos are not the special metal fancy type, hence recommended change interval is shorter...

 

Turns out it may have been the coil(s) the entire time. I cleared out a lingering ABS code and the other codes have not returned nor have there been any errors. I'll update if they come back. I kind of hope they do - I can't return the ABS sensor and that thing was $300.