I have a 2011 Cayenne S with 146000km/90K miles. I have been having this enging knocking noise intermittently now for the last several weeks. I can only really hear it when the car is iddling, and it comes and goes. I also can't hear anything unusual when I open the hood. Wondering if anyone has an suggestions or any ideas of what this might be!

 

Where on this planet do you drive the car and what octane and fuel brand are you filling it with? Is it knocking under heavy, medium or light throttle input, is the throttle input rapid, moderate or slow; or while at cruise?

Are there any modifications to the engine or engine modules? Any recent repairs?

 

the video is far too quiet for my computer speakers to play usefully.

Could very well be the fuel vapor purge solenoid or the leak detection pump. The LDP is on the passenger side rear fenderwell (on the charcoal canister) but the noise travels up to the center console.

 

Run the vehicle in Vancouver, Canada, always on 91 octane with synthetic mobil oil 5W-40. No recent repairs to the vehicle, no modifications. I just got a misfire code today on cylinder 4, so will be taking it in for that, but this idling noise i attempted to demonstrate predates that by several months (sorry, i know its not great but its a close replica of what it sounds like inside). I cant hear the noise on acceration or reving of the engine, only when its idiling, and it comes and goes (though it has certainly become more frequent lately).

 

the video did not show on my screen the first time I responded.

The rhythmic noise that I can hear is more than likely the tank vent purge valve. Mine was replaced in 2020 and sounded just like that. I do not hear it any more. I have either tuned it out subconsciously or it has "broken in" and become quieter. It may be noisier when it is colder outside until the engine compartment gets fully heated up.

I am going to guess that the misfire code is the coil pack. A simple test my tech did was to swap cylinder 3 and a cylinder on that same bank and see if the misfire code moves. My first one failed at 75k miles. about 5k miles later I replaced the remaining 7 for peace of mind since this is my wife's grandkid hauler.

 

Awesome, thank you so much for your help - taking a look at this more I think youre most likely right here!