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    PASM again

    Am I going crazy? First, I noticed that my 997S was bouncing softly while going over a 5 cm garage door sill. Now, I feel as if the back of my C2S is bouncing softly while driving at normal speed over uneven pavement. Has anyone heard of PASM misbehaving like that without showing any error message on the display?

    Re: PASM again

    what is your Porsche's model year?

    I have heard some of the 05 MY pasm misbehaving like what you described, maybe you should drive it to the service center and check it out.

    Re: PASM again

    Malmsteen, my CS2 was delivered in October 2004. Where can I read more about this issue?

    Re: PASM again

    wtsnet is the Rennteam expert on misbehaving PASM after his experiences with his '05 Boxster S....

    Re: PASM again

    Oooooh yes....

    How would I describe it? Unsettled ride when you expect it to be solid. Precision of steering lost, almost feeling disconnected. Jelly-like wobble of body when turning sharply or traversing small steps as you mentioned.
    And sometimes feeling that the suspension is a bit harder than is should be - more thuds from rough road surfaces being felt in the cabin - even though you are driving in a relaxed way.
    No error messages, and nothing logged.

    I had my rear PASM shocks changed first, but that didn't help much at all. The later I had my PASM control unit changed, which seemed to make a larger difference, but it still acts up a bit. Before it used to become down-right dangerous.

    My current theory is based upon the handbrake binding a bit. Does the handbrake feel slacker than usual? Does the rolling resistance seem more than usual? Is your fuel consumption a tad higher? Does it make a difference to handling if you pull the handbrake on slightly and release it when the car is moving forward slowly?

    Trouble is, my experience of technicians is that they have little time/experience/enthusiasm available to devote to your problem, and will usually pass it off as 'It seems like it's behaving normally to me!'

    Share your observations, however vague, and that'll give us more of an idea of what's up with it. Or not! I feel your pain though. You know something's up, but can't pinpoint the cause.

    Re: PASM again

    wtsnet said:... My current theory is based upon the handbrake binding a bit. ...

    If the hand brake was binding it would heat up and fry itself. You would smell it and eventually the binding is no more and the brake does not brake any longer.

    I agree, PAG blundered PASM, both the technology choice and their implementation. They should have licensed the MR tech from GM/Delphi - that works just fine.

    Re: PASM again

    ADias said:
    wtsnet said:... My current theory is based upon the handbrake binding a bit. ...

    If the hand brake was binding it would heat up and fry itself. You would smell it and eventually the binding is no more and the brake does not brake any longer.

    I have no sense of smell. And the heat generated is what I mean. I don't mean hard on, and maybe not all four, but just enough... maybe.... And my handbrake was always reluctant to hold on even slight hills unless you really pulled the brake on hard... and my handbrake felt slack.
    It's only a theory! In my experience, I can play with the handbrake and seem to experience a change in handling behaviour. If pawelmontana finds similar, then it's an observation towards the theory. It's worth considering.
    Interesting that pawelmontana's is also an early PASM car.

    Re: PASM again

    wtsnet, First let me state that I use my handbrake only once or twice per day. Parking the car overnight, the car stays in gear , but the handbrake is released. Generally, my handbrake holds the car uphill well, but only when I pull it all the way up with significant force (much more than on other makes of cars I had before). No burn't brake smell ever. Gas mileage is difficult to judge as I drive in stop and go traffic most of the time. No leaks or funny sounds from suspension, just jelly like behaviour in normal driving + car boucing and swinging when going over garage door sill. No PASM FAILURE message ever.
    Can the PASM s/w be easily updated at Porsche? Maybe hat could help?

    Re: PASM again

    No, I believe you have to replace the control unit itself.
    My 'theory' is that the handbrake cable might be corroded, and not releasing the pads from the drums on the drum brakes as much as they should, leading to 'glazing', hence not gripping well on hills unless you yank the lever right up hard. Since my playing with the 'applying the brake whilst moving a bit' the brake has been a lot grabbier.
    Seriously, try it. Just because you never leave the car parked with the brake on doesn't mean the cable can't seize up. Maybe!



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