This is what I am thinking of sayign the the car when I hear what appears to be an audible warning coming from my instrument cluster at right around 100 mph ...this is super annoying! I heard this before and thought it was something else or triggered by agressive pulls in 3rd or 4th gear... then I took it into a reputable shop and today and went for a test drive with the owner and he pointed out that it was an audible warning sound coming from what appears to be the instrument Cluster when the car reaches right around 100 mph, has nothing to do with excelleration just the speed at which the car is traveling, everything else is solid, chassis, suspension, engine, brakes etc, it definately sounds like it's coming from the cluster....it's like a "whaaaaaa" continual howling/humming audible sound...it's annoying...the car still goes like hell but the sound is still there...

this is perpelxing to me...anyone ever heard of this or know of something like this...I'm stumped about this! ...any help or advise would be appreciated, thanks all!

 

Any way to make a video of the noise? Have you dynoed it, does it make the noise if you hit 100mph when the car is stable?

 

I think you can get rid of the audible warning by adjusting the maximum MPH with the stalk that is used to check oil and change other settings. I set mine as high as it would go on my 02 996tt. Hope this helps, Dale

 

You have to go into the on board computer to alter the speed warning.

 

I have heard of that - setting a mph on the stalk using the cluster menus but that is a 'ding' with the set speed limit and a circle wit a diagonal line across it...this one on the other hand is a loud whirring sound ''whaaaa" that comes from the cluster... or what appears to come from the cluster...it's seriously purplexing....

I'll maybe try to get a buddy with an iphone to do a vid maybe over the weekend or something...while I drive... it only happens at right around 100 mph and it doesn't matter how you get there, hard 3rd or 4th gear pull or steady climb in 6th...same noise...

Tj haven't dynoed it, dunno if it's load dependent but that's an idea...maybe I will need to do that...

 

Does it have that aircraft "dong" sound. the one when the cabin crew come to serve you if you push that red button.
That's the same sound you get form the speed warning you can set up in the PCM and the dash stalks. There a pain in the @ss. They don't stop you speeding but just give you an audible warning when you reach a threshold you have set. There are 3 programmable speed warnings. Each with its " dong " if you pass it and when you come back below it.
The dong is not constant all the time you are over the limit . IIRC its just 2 "dongs" when you go over and 2 when you come back down.
You can check box them to not work if you want. Most people dont use them.

 

No it's not a 'ding' sound or a 'dong' sound or beep or buzzing...it's a howling or whirring sound...almost like a droning 'waaa' type sound...I am totally perplexed have no idea what it is...the shop said it was from the cluster and it sounds like it, when I hear it go off...I could mash the pedal and take it to 100mph or thereabuts and it happens never lower, most likely the sound will keep on past 100 but on the street here I don't want to push my luck so I slow down...the gear it's in doesn't matter and the aggressiveness of throttle, hard or steady doesn't seem to matter either...

 

So you would say its more a mechanical sound rather than an electrically generated one.
Just behind the dash in the trunk is the ABS/PSM unit (pump) and also the fuel pump is not far away and can be heard when they start to whine.
Do you get the sound if you creep up to 100. ie don't use boost?
The pump might be getting worn and when you come on boost the FPR will restrict the return flow of fuel to raise the pressure, hence load the pump up??

 

How about an air leak into the cabin behind the dash? maybe from a missing grommet or plug, therefore, gear selection doesnt matter, but the speed does

 

There is a big rubber gommet behind the battery on the drivers side. Maybe it is gone or not inserted correctly. Windshield leak??

 

It is your speed warning. Use the smaller stalk on the left side of your steering column to adjust. Navigate through the menu (as if you are changing your oil) and look for the speed menu and change it to a much higher speed. Mine is at 130...you know for testing purposes...

 

The fuel pump would make that Waaa, sound, but you should be able to get that same noise if you would go through the gears, ie) hit the same RPM as when at 100mph, but this seems not to be the case. If the ABS/PSM pump was making that much noise, I would think you would get a warning or a total shut down of the system.

I would pull all the carpeting up under the bonnet, and take a look for any gommets missing or put in incorrectly, that is cheap and easy to start with.

If you dont find anything under the bonnet, I would take the hit and dyno it, get to the 100MPH mark and see if it happens at wheel speed or if it is 100 mph air drag speed.

If that doesnt work you could give the car to me and Ill deal with the sound

 

That's actually a great idea.

 

You guys are great, thanks for the input and advice...you guys are definately thinking outside of the box, things I didn't think of...keep it coming, and thank you.

I defiantely will have the ABS pump and the fuel pump checked otu to elimiate those as options as I work to narrow this down...

Checking for air and grommets is also something that I think it could be...

As aonter data point - One thing I do recall is that the original owner had the windshield replaced (some minor chips and scratches, he didn;t even need to but he threw in a new windshield for me just to make sure we'd have no problems at State inspection for registering the car). The installation and glass were supplied by a by Porsche authorized local glass subcontractor using factory original GT2 windsheild... maybe that could have something to do with it, but the windshield looks solid, no leaks, or anything like that...could it be the weatherstripping around the windshield

The noise is not one steady pitch or constant...it's almost like a harmonic whine that's coming from right infront of you it feels or sounds like, which is why it "appears" to come from the cluster...it can be faint, it can increase in volume with a few more mph etc... it's not rpm driven, it seems to be solely speed driven, occuring at right around 100 mph or thereabouts...it doesn't happen at 70, 80, 90...but as you creep onto 100 there it is! ...the dyno idea would be able to eliminate air seepage somehere I suppose...? Ugh this is frustrating! lol

 

I read the manual this morning and it talked about that, the audible sound for a set mph along with a display on the cluster with MPH and a circle around it. What I have isn't that, it's not an audible 'ding' with a display it's a harmonic whining sound...the guy at the shop went thru the cluster using the stalk and checked for the set speed marker and couldn't find one or he cleared it - after my test drive we pulled the car back into the shop and he got out a computer looking tablet and I think that is what he did with it...he was working through the cluster pretty quick I really couldn't tell...