Christof6447

Can any one please help me with my issue
I recently have a knocking sound which comes when driving on a bumpy road around 15 - 30 mph
I have just had an 8 year service done on the car at OPC and they have replaced the front anti roll bar bushes.
This is not solving the issue. I did get new side skirts fitted could a hose maybe have come off or un-fixed ?
What is under the under trays anything could be loose under these ?
Anyone know how I upload a video ?

Jack F

GTS side skirts or something that was cobbled up? You have the shop drop the trays and see what’s going on. I assume you are in the UK. OPC is the Porsche dealer service center?

Christof6447

Hi Jack

No OEM from OPC. The originals were badly damaged with gravel rash so I replaced them.

I am in the UK

Yea I got an 8 year service done and asked them to check the knocking noise and the replaced the front anti roll bar bushes as these were done.

the knocking is still there

I have a video but cannot seem to be able to up load

Jack F

What does OPC mean? In the US we don’t use this abbreviation.

Christof6447

OPC is an abbreviation for an original Porsche garage / work shop / centre.

that’s all.

SilverSFR

US = Porsche Service Center

TomiK

I have a similar unsolved knocking from the rear. It occurs over small bumps, as well as when sharply changing direction (like slalom driving). Dealer first thought loose airbox, so the first "repair" was unsuccessful. The car is going back in on Tuesday so I'll report back. On the test drive, the Tech said the noise is definitely from a "component" and suspected either the shocks or the engine mountings.

Christof6447

Thanks for the info. My car has just been for a service and the Porsche centre replaced the front anti roll bar bushes under warranty however this has not made a difference my knocking sounds as if it’s coming from under me like a loose under tray. As I mentioned I changed both side skirts as they were badly gravel rashes after doing the north coast 500 ( 500 mile trip round the top of Scotland in the U.K. ) since then it’s been this knocking. Any idea what pipes run under the under trays I was thinking maybe one has came loose and banging on the floor.

BSO

Not had my Porsche with this problem but my Mercedes’ SUV had a similar issue when new and they replaced 3 of the struts to resolve the problem.

No reoccurrence for the following 8 years of ownership.

TomiK

Just an update after the car (2017 991.2 S) spent 5 days at the dealer. They traced the noise to the dynamic engine mounts and replaced both. There were no fault messages, just a thunking noise that became more frequent the more I drove.

Glad to have CPO warranty as it was a $3000 job.