3.2L V6 One sided "rattle" above 3000 rpm

[CayenneNL]

I have a 2004 Cayenne, automatic transmission is fine, fuel consumption absolutely fine, no real strange noises. Unless you go beyond 3000 rpm.

When stationary and revving beyond 3000 rpm a rattle/not so normal noise is heard only on the driver side of the engine.

I read posts about replacing the upper tensioner (using a 3.2 V6 VW Touareg part which is cheaper). Does anyone have any experience with this? Car was sluggish a while back and got 6 new spark plugs which made it run as before, just the problem above 3000 rpm that occured since. I have only driven a couple hundred miles with this noise now any advice would be welcomed. As I said I have not noticed it unless I go above 3000 rpm, fuel consumption has remained the same, no warning lights or error codes. My local garage "read" the car and no error codes were displayed and nothing could be found apart from this typical noise.

l

It is not a US car, I am based in the Netherlands, Europe.

[Loren]

Check with your dealer/OPC as there are a couple of TSBs for rattling noises - which may be related to your noise.

Also on a car this old you should likely get the coil packs (for the spark plugs) upgraded to the latest version (to prevent power loss and misfires)/

[CayenneNL]

Thank you Loren, the OPC has no idea what causes it, they send me to the VW garage. Car has always been in OPC for maintenance since 2004.

[Loren]

(click to enlarge)

[CayenneNL]

I had a good listen and look this weekend, its better to hear when the engine is just started and cold. And once the engine is warm its easy to hear when you go above 3000 rpm. But only on the driverside of the engine.

Could a fuse affect 3 cylinders or is this more a case of a chain tensioner? I have no loss in mpg, it also drives normal and goes smooth on the highway (70-80 mph / 120 kmh).

[wvicary]

The main engine timing chain tensioner can give issues and cause noise, it's easy to replace so start there. The timing chain between the camshafts is another matter. Possible to get a sound clip?

[whiz kid]

Hi guys.  On the 3.2v6 there is an issue with the air intake manifold, under the plate with with the torx screws.  From inside there is a loud rattling when the engine is revved hard. Unfortunately this part seems bonded to each other and I'm not sure what purpose the screws serve as you can't look inside it !!!.... below on the same part is the long round air intake control flaps which are vacuum operated under rev range.

 

I originally thought the timing chain may be at fault because of the noise, but it is definitely inside the air intake manifold.