Hi everybody, my car is a 3.4 tiptronic 996 1999 and has been making this strange noise. When it's cold everything is fine but as it starts warming the ugly noise shows up. My mechanic told me that it could be the aftermarket header (ebay header) badly installed or leaking or something like that.

What do you think? Is it an expensive repair? Should I worry more than I am now? Please help!! Below is the link for the video. Thanksss

 

Doesn't sound like an exhaust leak. But you have to give weight to your tech and eliminate that possibility.

Sounds more like a bad idler roller bearing. My 996 Turbo made a similar sound, though not as loud, and it was an idler roller bearing. Had all of them along with the tensioner replaced. Might mention the first time an idler roller bearing went bad the sound was different. The first time I heard a "dry bearing" sound and sure enough it was an idler roller right up close to power steering pump.

You can "test" the idler roller bearing theory if you want by removing the belt and starting the engine and letting it idle only long enough that the noise should be present and is not or the noise is present.

Be sure you carefully note the belt's routing and the direction the belt rotates if you intend to reuse the belt. Even if you replace the belt you had better remember the routing. Draw a diagram or take a pic or 3.

 

Thanks Macster for your answer, I'll check that.

 

Macster, is this the idler you are talking about?

 

The item in the picture appears to be an idler roller and its hardware.

No way I can tell if it is the right one for your car.

When I've had the ones in my Turbo replaced the tech selected the part # based on the car's VIN.

If you have id'd a bad idler/tensioner roller then you can remove that one and mosey on down to the dealer's parts department and get one just like it.

There are online sources of Porsche parts, too.

 

Thanks again Mcster I really appreciate your help