Hello,

I recently purchased a 2018 PCNA Porsche Panamera 4S with 9,000 miles. When driving aggressively in any mode, normal, sport or sport plus, I often experience a sudden grinding noise and loss of brake pedal feel while taking a corner at speed. Just the lightest touch of the brake pedal can make grinding noise and jerky loss of brake feel appear. It happens mostly at speed, but can occur in the 30-40mph range too. I first noticed on a spirited test drive before I bought the car, but dismissed it. I have noticed it on the curvy sections of Highway 2 heading north to Pasadena, but experience most frequently while driving aggressively on the scenic section of Los Angeles Crest Highway (Hwy 2) heading up the mountain and down the mountain.

I was thinking traction control, ABS braking or transfer of the drive power from rear to front wheels was the problem. It appears to be just the drivers front or drivers rear that is affected at any one time. I took it to my local dealer and of course they can't replicate it driving civilly around the block. I think it is a flaw, either mechanical or software related, and can't believe it is operating the way Porsche intended.

If my dealer is telling me it is a normal function of the ABS and I disagree, what options do I have to get it fixed? It bothers me so much that I don't want to own the car if it can't be fixed. I submitted multiple videos to my dealer showing the sound and speeds when it occurs.

Videos are too large to upload. Here is a dropbox link to download the videos: https://www.dropbox.com/sh/63dnpiwqq...UWTdWZnaa?dl=0

Thank you in advance for any help.

-Chris

 

I watched the videos and can hear a clunking sound. I can't tell there is brake fade, but that is hard to show in a video.

I'd check the brake fluid level. Make sure it is below the maximum line/marker, (above the minimum line/marker as well). Let's start with that.

 

The dealer has it still and they inspected it, but I will also check. Thank you.