aerolithe

Good day and thanks in advance. I am looking to buy a 957 turbo and would like input from you guy regarding the engine noise. If you listen to this video do you hear anything special?
This a Cayenne Turbo with 155000 km
Marc

brett968

I don't like what I'm hearing at all. It sounds like there may be some piston slap from early stage cylinder scoring. The first second and a half of the video is most telling. When you get the camera in close the injectors and other engine noises drown out the troubling sound I'm hearing. Personally, I've heard enough where I would avoid the car. If you're on the fence, consider taking another video but this time position the camera to the side of the vehicle near the fender well maybe 2 feet off the ground. I've found this location attenuates other engine noises and lets you hear piston slap more clearly. Once you've experienced this problem on one of these cars you quickly develop an ear for it.

95_993

The rapid clatter of injectors doesn't bother me but the faint knock does not sound good

Vivid7

I listened to it through my powered studio monitors. I don’t hear anything questionable. high tick is the injectors. I don’t hear any clacks or low frequency noises.

v10rick

Sounds normal.

If this is a local Cayenne, due to the climate in your area, its best to bore scope the cylinders as a precaution.

RazMan

I have to agree that there is nothing unusual there - just injector noise which always seems worse with the bonnet (hood) up

oldskewel

If anyone out there has a Cayenne V8 that runs WITHOUT any suspicious sounds, I'd really like to see/hear it. It would help distinguish the problem ones from the others.

To me, the clip does not sound perfect, but I've never heard perfect. So maybe I'm expecting something that does not exist.

Here's the clip of my 2004 S, that I posted when doing my PPI:
https://rennlist.com/forums/cayenne-...l#post14675228

Suspicious sounds, others on here had their doubts as well, more complete PPI and oil analysis showed good, 2-3k miles later, no problems.

sprfrkr

I clicked through because I always thought my engine was louder than it should be. Sounds like your video. 2010 GTS which should not have bore scoring issues to worry about.

dr914

boy I cannot hear anything except maybe a roller making noise

aerolithe

Well thank you for all your comment I will go and take a second look and see I will keep you posted.
I look on Youtube to hear some engine with noise and would like to know thee build sheet of their Cayenne or the engine code so I could check.
Vin # WP1AC29P48LA94772 Build date is January 1 2008

brett968

I'm a bit surprised that only two of us hear something concerning. There's a tat-tat-tat-tat sound (about 250 bpm) that sounds a lot like early-stage piston slap. I'm not saying it is for sure but I'd definitely investigate further before considering purchase (glad to hear the OP is doing this). Like I mentioned earlier, it's easiest to hear in the first second of the video before he moves the camera in closer. Also keep in mind that cellphones are not precision audio/video recording devices. I've recorded a Cayenne with piston slap using different recording devices. With one phone the piston slap was barely noticeable while with the second phone the piston slap was clear as day. I have found that placing the recording device in the location that I indicated earlier is the best way to ensure that the piston slap noise is captured.

oldskewel, I watched the clip you linked to. There is some faint strange noise that I can't identify but I do not hear anything at all that resembles piston slap.

January 2008 build date, 155,000km (96,000 miles). Tat-tat-tat sound. I'd be nervous!

oldskewel

Great news for me. Thanks!

You certainly sound like you've got a better ear than I do for this stuff.

For the OP, as I went through in that thread, there were a number of steps I did to try to rule out scoring, prompted by that suspicious noise. The only thing I'd do differently would be to invest in a higher quality (resolution, brightness) endoscope for the surface inspection.

aerolithe

I just track down more information about that car and found out that somebody remove the engine and been having to 8 sleeves, new main bearing, new rings in and put back the engine together.
I would like to know if that a good procedure and if anybody have idea of longevity of this. Estimating they deed fallow all good procedure????
I am thinking to her her pass...The rest of the car is great

brett968

That makes me even more certain that I heard piston slap. Only in this case, rather than being due to cylinder scoring, it is likely due to the use of forged pistons and/or the piston to cylinder wall clearance. It is not necessarily a sign of a problem, particularly if the engine was cold when the video was taken. However, I'd probably still pass on the car and only consider it if a) it was a killer deal, b) the pedigree of the engine can be traced to a very reputable engine builder, and c) all the work that was performed is fully documented.

Burnt McGurnt

Oldskewel IMO these engines are quite loud with the hood open. It's mostly injector noise which sounds like a sewing machine. Here's a quick video of my 2010 GTS with 75k mi, no knocking, bore scoring or piston slap just injectors coils and all the normal valvertrain noises. I pass by each cylinder, ground level, both wheel wells.

FWIW to the critical ears the slight knocking sound at the very beginning is not audible in person.

https://www.dropbox.com/s/65r7sihe35...75332.mp4?dl=0