Did you by chance find it? Or do you know how to access it?

I searched the PET for "yaw" "acceler" and "sensor" and found nothing like a yaw sensor or accelerometer :-(

 

I don’t recall, shame. I would really appreciate it if you would update this thread if/when you move forward. Thanks.

 

I started to write an answer, and it started to become a question ... .

Anyway, I'm not sure I have. I haven't tracked this particular car yet (and no, I'm not in a rush to turn off PSM the first time I do). Nor have I attempted drifting it yet (which, on the other hand, I am eager to do before winter ends), for many reasons (including believing that even with PSM "off", it wouldn't let me).

But is this true? Until a few weeks ago, I thought so. Amoung other things, I recall recently reading somewhere that it triggers when the car senses sufficient g forces (which seems odd, so I assumed the author meant yaw angles).

But in reading how to disable it, I don't recall this being confirmed. Maybe mentioned (not sure now), but certainly not in detail. On the other hand, it seems fairly well established that if one (front?) wheel triggers ABS, PSM will come back on. Is this the only thing that will make it come back on? Can I go drifting without diabling it (if some more snow would kindly fall)?

(Don't worry Ahmet, even if I can drift, I'll still try disabling it sooner or later and post what I know. But it would be very interesting to know whether something other than locking a wheel can trigger it while turned "off".)

 

Interesting PSM article from a racers perspective

http://www.deter.com/porsche/PSM.html

 

My experience:

With PSM disabled using the dash switch and you’re NOT on the brake pedal, no intervention, period. You can spin the car 360 degrees, do on throttle drifts, pitch it sideways and whatever you want, and it wouldn’t do anything unless you touch the brake pedal in which case it’s fully and completely active until you let go of the brake pedal and/or the car is no longer under a condition that triggers PSM intervention - more on this shortly.

My educated/researched -and to the best of my perception- thoughts on STABILITY intervening requirements (while system is disabled through dash switch) are that:

You must be on the brakes (even lightly), and one of the following:

Yaw angle sufficiently high,
At least one front wheel at impeding lock up.

To further expand on why one would want to disable the PSM such that it does NOT intervene at all ---> In a nutshell, if you want the car to rotate under braking. You might want this to tidy up the line into a curve or a mid curve yaw angle adjustment (possible small performance benefit, if you have the skill). Or, you might want to get the tail to come way out under brakes, to then transition to the gas pedal for a long drift, or mid drift adjustments (certainly slower, no performance benefit what so ever on a paved surface). In either case, for me it was for personal preference.

*One of my 996 turbos intervened far earlier than all the other 996s I've owned or otherwise drove or rode in a setting that would potentially trigger stability intervention. I’ve been tracking and instructing for a long time so these included a 2003 C4S, two other 02+ turbos and several 02+ Carreras, so I believe that particular turbo had a faulty yaw sensor as best I can tell. Less likely but possible that the steering angle sensor was not calibrated correctly or otherwise faulty. I mention this in case somebody reading this post finds PSM entirely too intrusive, while others do not. When everything is working properly and the system deactivated through the dash switch, you must push the car hard before you’ll feel the intervention. This isn’t like a late 90s or early 2000s “normal” car, which are entirely too intrusive, even on the street.

 

Great article about PSM. Maybe I'm just too aggressive through turns 7/8

Seriously though, I think it's the trail braking that reactivates the PSM, which then interferes with my driving style. What's wrong with a little slide around a corner? It can really help to rotate the car into the direction you want to go.

 

I can confirm this. I recently did an autocross that was used a lot of a banked oval and subsequently had a decreasing radius turn. This is where I'm used to using heavy trail braking, drifting the car in under braking. When I tried it in my 997 with PSM "off" (liers), it was an understeering nightmare. So I'm looking for a way to disable it for track days.

I saw mention of putting in a switch on "the ground wire" of some brake cable (???). Can anyone point me to a thread that talks about it? I'm Googling in the meantime...

 

10) buy a 996 without it


Anyway, not a crazy driver here, but it is fun to kick the rear end out a little whne it's wet and have fun with it. Dry pavement I'd never come close to needing it for almost all the stuff I do.

 

Any updates on this?

 

Not really. I did unclip the brake fluid sensor and sure enough, lots of warning lights came on. And probably I could get the rear a bit looser too. But shortly after doing so, I found myself heading off for a long highway trip in the rain, so I clipped it back in. And it was a bit of a pain to get to, so I decided not to unclip it again till I had a chance to play with the car in appropriate conditions.

Hopefully I won't have to wait more than a few months, and hopefully I'll remember to post an update. Feel free to remind me, though ...

 

I've always assumed I never had PSM because there is no button on my dash. PSM wasnt standard in 01, was it?

 

I think PSM is always an option and not std.

 

The Bentley book says PSM was standard on C4 from 1999 and optional on C2 from 2000. I don't know if this is a reliable source for this.

 

I've had some butt clenching moments in the canyons and no button. I'll just assume no psm. hah.

 

Bumping this thread. I've been running "option 2" but I'm looking for a better solution, one which doesn't result in what I call "over active ABS syndrome" my ABS triggers far too easily and often.

Has anyone tried wiring a switch to the yaw sensor or the PSM computer? Any write ups?

Thanks!