amlk

I'm having some weird symptoms with my 997.1 Targa 4S.
When driving in "normal" mode i'm getting the "PASM Failure" each time after few miles. It resets after restarting the engine.
This Failure never happens when driving in the Sport-mode only in normal mode.
Error messages says that there are PASM valve error in three shocks. I guessing that there cannot be three valves broken at the same time.
Any idea what could be the real problem? Anyone has resolved similar issue?
Thanks for your assist in advance.

Petza914

What are your wheel and tire sizes. When in sport mode, the electronic nanny of PSM is loosened up a little. Because your car is all wheel drive, PSM is monitoring your front wheel revolutions relative to your rear wheel revolutions. If you're running non standard tire sizes, I bet the rolling circumference is off just enough where in normal mode you get the warning and in sport mode with the relaxed slippage threshold you don't. If this is the cause, that's also not good for your AWD transfer case as it's trying to slip one axle or the other all the time to make them rotate at the same speed.

Normal sizes are 235/35-19 F and 295/30-19 or 305/30-19 R

Edit: Sorry, I misread your error as a PSM one. What I described here would not apply to a PASM Suspension error. That is odd. I wonder if when it tries to initially stiffen the suspension, one of the shocks doesn't respond accordingly so you get the error. Seems like it that was the case it wouldn't work right in regular mode either and you'd get the error all the time, not just in sport mode.

Fahrer

How many miles on the car? It could be worn shocks.

jamesinger

also, when you do press sport mode when you get the error, do you feel a difference in dampening?

amlk

Car has 180k original miles on it. It has replacement engine but I don't now if the shocks has been replaced or not. When the error appears the shocks gets stiffer than in the sports mode. At least in low speeds it feels much harder. Is there any way to make sure if the shocks really are worn out?

Hella-Buggin'

I have had this happen when the battery died. It was old and even though I recharged it the voltage was just weak and it kept happening until I got a new battery.

Fahrer

As mentioned above, it could be a battery issue. I should say that when my battery was getting weak, the instrument panel would display a PASM error on start-up but this message always went away as I drove the car with no other symptoms. It could be that that the system is seeing the worn shocks (with non-standard behavior due to the wear) as a failure. If your battery is more than 4 years old perhaps it is worth replacing or having it tested. Otherwise a dealer or good independent Porsche mechanic can diagnose the issue.

amlk

Battery has been replaced few weeks ago and it didn't fix the problem. To me the best guess is work shocks. Just wondering that is there a way to check them. Replacing all four shocks will cost couple of thousands so I don't feel like spending that without a good reason.

BucketList

OP does the car have a DSC controller installed? Your error was for 3 shocks but the OEM controller is a single channel controller. Just wondering if it could be the controller.

jamesinger

If it is defaulting to full stiff, that is not just an instrument anomaly. That might be obvious but that is why I asked if your suspension feels stiff. Proper PASM errors make the shocks go to full stiff. If I were in your position, I would go to my indie or suspension guru. I do not have the technical skills to go beyond that basic diagnosis.

Bruce In Philly

If you think it is the controller, you can swap one with someone else in about 10 mnts of work.

Peace
Bruce in Philly

Prairiedawg

If its thousands for shock replacement, why not take it somewhere for a proper diagnosis? It sounds like you have gone as far as you can short of swapping the PASM module.

DG.DG

Had PASM failure, car ran full stiff in all settings. Error code was to front right. Bought two new front shocks. Put the new one in the frunk and plugged it in to test, didn't want to install if didn't fix it. Cleared error codes, think even drive around slowly to confirm.

Installing the front strut on a 4s was one of the toughest repairs I have done. Get a clamp spreader if attempting DIY, wish I had one.