I know this may have been discussed, and may be a common issue, but search doesn't turn anything up under chatter, suspension, etc.

Anyway...

something in/or around the right front wheel area will "chatter" once, maybe twice, when braking. It only does it when the speed decelerates to somewhere under 5-8 mph. It seems to do it most regularly when really hard on the binders, (but it has happened even in reverse, if you "hit" the brakes, esp. if the front wheels are going over a bump at the time). It's almost like an ABS doesn't "let go" until the wheel has already completely locked up? (It's kinda hard to explain...when I first heard it, I wondered if it had even happened, but now I know it does).

It's like the right-front wheel "jerks", once or twice (depending on how much is demanded of it). The tire may, or may not, squeel for just an instant...(I believe this depends on how much "mo" you've got going at the time")

My dealership maintence manager told me today that he'd never heard of such a thing (but to bring it by wed, and they'd check it).

Can anyone tell me what this may be? Has anyone ever heard of such a thing?

Thanks for any help...
Dave
forgot...it's an '06 997S w/ 5k miles.

Which brakes? The regular red caliper w/iron rotors?

Yes Edgy, they are the regular red calipers. Standard brakes.

I read one other post (500) who had what sounded like a similar problem and it turned out the swing-arm on his car needed "tightening up"

Anyway, just wondering if anyone else has any clue, just in case I can't get it to do it for the service guy tomorrow.

So, does the car feel normal in all other aspects? If it was a loose swing-arm bushing, I'd assume that you'd have tracking issues when at speed and off the brakes.

I would also think that any issues with the ABS sensors would set a fault code; if the light is not lit, the sensors are probably OK.

It could be a logic issue in the ABS unit, but that's unlikely bc only one wheel has the issue.

I'm wondering if it's a mechanical issue with the right front caliper - maybe the pads are hanging up, or maybe some foreign object is stuck in the caliper... just brainstorming at this point.

If the car tracks and steers normally under other circumstances, I'm thinking that it's a caliper issue at the right front corner. BTW, I'm not a Porsche engineer - but I am an engineer - and no, I didn't stay at a Holiday Inn Express last night. <g>

I'd be interested in what the dealer tells you, Dave.

-don

how are your tire pressures? if they're uneven from left to right, you could be confusing the ABS.

It was loose strut bolt.

Dan, Don, insite...

Good thoughts all, and thanks for your input. But your assumptions were all wrong (if you were assuming a competently safe driver).

The first thing that happens is the service mgr drives the car, and I have to tell him how to "make it do it". He feels it too. So, we go back and they hook up a computer that monitors ABS, and now another drive. The ABS checks fine. Now, they check the suspension, all's torquey dorkey there. Still does it. By this time, the service supervisor is looking a little perplexed.

We get into another C2S and try to duplicate the problem in it. BINGO! It does it too, everytime, if braked THAT hard to a COMPLETE stop.

They said to fix the problem, the driver needs DE. Then they sent me home. No charge.

Dave, that's funny. If you sign up for PDE, let me know when you go, I'll join ya...

-don

Well, sometimes it IS the driver. Recall that most of us are merely a product of high school drivers training. And then a little word of mouth within the Porsche Club....

Glad to hear it is fixable!