991.1 (2012) Clacking and Popping Issue.
#1
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New here and hoping to get some help from the community. I have a 2012 C2S (991.1) that seems to have a strange noise coming from the front end. The car is under a Certified Pre-Owned (CPO) warranty, but the CPO is only useful when an issue is identified. In my case, no one seems to be able to diagnose the problem.
I’ve taken it to both Porsche and a highly recommended third-party shop, but neither can identify the issue or reproduce the noise.
The issue is a clacking/popping sound that seems to come from the front end. It happens consistently when slightly turning while going up an incline and under load—for example, when I’m leaving my underground parking. The incline is about 4%, and there’s a right 90-degree turn that requires me to veer slightly left for a wider angle before turning fully right. I usually stop to wait for the gate, and when I start to move, I veer left slightly—that’s when the noise occurs.
I’ll attach a link with video as the file is too large to attach.
Any insight or help would be much appreciated.
https://www.dropbox.com/scl/fo/3ygnxl2v7sh5hvssjoeif/AGxiFYi7tD0dgXFBB-ByrR4?rlkey=cfkqn962booatcvc6v4lpyezn&dl=0
I’ve taken it to both Porsche and a highly recommended third-party shop, but neither can identify the issue or reproduce the noise.
The issue is a clacking/popping sound that seems to come from the front end. It happens consistently when slightly turning while going up an incline and under load—for example, when I’m leaving my underground parking. The incline is about 4%, and there’s a right 90-degree turn that requires me to veer slightly left for a wider angle before turning fully right. I usually stop to wait for the gate, and when I start to move, I veer left slightly—that’s when the noise occurs.
I’ll attach a link with video as the file is too large to attach.
Any insight or help would be much appreciated.
https://www.dropbox.com/scl/fo/3ygnxl2v7sh5hvssjoeif/AGxiFYi7tD0dgXFBB-ByrR4?rlkey=cfkqn962booatcvc6v4lpyezn&dl=0
#2
Rennlist Member
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Acorn effect or "Ackermann Effect". and if so very normal when turning slow. Find a spot and at slow almost stopped rolling speed make a tight circle and see if the noise shows up. usually will in reverse and sometimes moving forward. Search google for Acorn effect Porsche or Ackermann Effect Porsche. Both will point to Rennlist threads info on the topic. =Google will point to YT videos as well so you can hear and view the sound. This Ackermann Effect is a Porsche "character" feature and designed that way on purpose. If you really want the technical details on why it happens and the reasons Porsche designs our suspensions this way see link below.
Acorn or Ackermann Effect
Acorn or Ackermann Effect
Last edited by SilverSFR; 08-30-2024 at 06:55 PM.
#3
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We’ve ruled this out. The noise is a loud metallic sound, and even though the right-hand turn is a 90-degree angle, the noise occurs when only slightly veering left to take the turn at a better angle.
#4
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Did it just start happening, or has it always done that?
What brand tires do you have on the car?
Does it get worse in cold weather, in warm weather, or is there no difference?
Front strut mounts might be worth looking at, but failing that it does sound like the 'acorn' noise that results from lateral tire skipping.
What brand tires do you have on the car?
Does it get worse in cold weather, in warm weather, or is there no difference?
Front strut mounts might be worth looking at, but failing that it does sound like the 'acorn' noise that results from lateral tire skipping.