Crazy 996 brake problem

300cd300sdl911 · 08-05-2015, 01:06 PM

So here's my sad story. A couple of weeks ago my brake pedal was soft to return. Eventually I had to use my toe to lift it back up to normal position. I noticed this when coasting to a stop, after applying slight brake, the car just did not 'free wheel' but rather felt like a piston had locked up. A short while later while going up a hill I began to loose power.... At least that's what I thought at first. So more gas, downshift, and still slowing down. 10 seconds later cars in the middle of the road frozen- all pads fully engaged.

Managed to creep off the road open hood and pull off vacuum line from brake booster - after release of pressure then able to creep down the road to my local garage. Figured we should change master cylinder. Stealetship wanted $1100. I bought an OEM part from our host for $99. My garage installed and test drove - everything seemed OK. On my trip home same problem. Again pulled vacuum hose off booster released pressure and crept back to local garage. This time I purchased a brake booster and vacuum line ( with check valve) again from our host and had them installed. That had to be it. On the ride home- same problem. Brakes locked up tight. Had the car towed to the stealer ship where it's been for over a week. They haven't figured it out yet. Any ideas?! Car is a 1999 996. Fresh fluid and new Pagid pads
several months ago. Wondering if maybe ABS thing has gone goofy??

300cd300sdl911 · 08-07-2015, 03:48 PM

So anyone have a guess.

BYprodriver · BYprodriver's Garage

Make sure they flush new brake fluid thru the ABS, & test to see which wheels are locking up.

300cd300sdl911 · 08-11-2015, 01:39 PM

Well the stealer ship called today and they seem to think the OEM brake booster I just had installed is no good. They are going to change out tomorrow. Stay tuned.

Zmonsta · 08-11-2015, 02:47 PM

you mentioned new Pagid pad several months ago, was it the same shop that repaired recently & did they flush brake fluids then?

rennworks · 08-12-2015, 05:49 PM

Not sure if this applies to your problem,but I changed the pedal arm bushings on a 01 because the pedal would stick.
warren

300cd300sdl911 · 08-14-2015, 12:49 PM

Yes full brake flush with fresh fluid when pagid pads were installed. Ran two DE's with the pagid pads with no issues. Problem seems unrelated to pagid pads and / or brake fluid.
Thanks

300cd300sdl911 · 08-14-2015, 12:50 PM

Hmnn pedal arm bushing. Will keep that on the list.
Thanks

300cd300sdl911 · 09-01-2015, 01:17 PM

OK stealer ship diagnosed my problem as the new OEM brake booster I had installed. They said it didn't fit correctly. So after the diagnostic charge and cost of the new Porsche booster I was out the door for around $2300. Left the dealership and got 2 miles down the road and the brakes locked up full on again. Guess their diagnosis was wrong!!

Pulled the vacuum line off- released pressure and limped it back to the dealer.

jwetering · jwetering's Garage

Good news - you get your 2300 back (@@sholes).

Do you have PSM?
Maybe it's confused?

Was thinking ABS, but it relieves pressure not the other way around. What about your master cylinder ? It could bind I would think.

300cd300sdl911 · 09-15-2015, 12:58 PM

Well looks like it's finally over. Bottom line - P dealer determined the OEM parts I had purchased and had installed (master cylinder and brake booster) were not the correct fit for my car. They were removed and replaced with genuine Porsche parts. Cost for parts and labor was $2800.

I've driven the car for several days now and brakes are working fine. Guess I've learned a hard lesson. Only genuine Porsche parts going forward.

amazongreenie · amazongreenie's Garage

Not knowing where you are in CT, *WARNING* : do NOT ever have any of your car(s) serviced at Imported Cars of Stamford, TRUST ME!