NYC_AREA_GT3

At idle and low revs, I seem to be having some vibration-sounding rattle coming from either the exhaust components or from the metal floor pan that's under the engine. I have SW muffler bypass pipes, so maybe that's coming loose, I can't tell when I bend down and try to pinpoint where it's coming from, but it sounds further forward than the rear muffle bypass pipes.

Anyone else had this / solved it?

Thanks

c4sdriver

Could it be the flywheel? That is normal i think.

MileHigh911

Sounds like PDK=S noises. Normal, Porsche wanted it that way. They quiet down when warm.

0to60

I think those NY roads have loosened something up.

NYC_AREA_GT3

It could be, but I haven't heard this noise in the last 1,600 miles, it only started in the last 25miles, and it won't go away regardless of temperature

NYC_AREA_GT3

Except I never heard them before, and they persist regardless of temperature

Mech33

I have the same issue, and I think it is gear lash / flywheel-related noises. Mine doesn't go away when warm either, and is loudest in 5th gear cruising at about 1800 RPM with a little throttle. Sounds like loud whirring noises. Quiet above 2500 RPM.

Shahano

I think this is just GT3 charm??

NYC_AREA_GT3

I haven't tried 5th gear at low RPM. Have you thought about trying to bring your GT3 in to get it resolved? I'm not sure what whirring means necessarily, but mine sounds like a metal vibration - like something is loose and rattling/vibrating while at low RPM / idle.

Mike in CA

There is definitely a rattle from the 991 GT3 gearbox/flywheel. It's normal for this car. It may vary a little with temperature but it is always there and I notice it primarily at idle. It sounds kind of like ball bearings rattling around in a can.

That said, the fact that for the first 1600 miles you didn't hear anything and now you do is a bit puzzling. If you never heard any noises at all before, I'd suggest that maybe you weren't really tuned in because all 991 GT3's have the gearbox rattle. On the other hand if you heard noise before, but this is a new and different one, maybe you do have an issue and should take the car in to have it checked. Let us know what you find out and good luck.

Mech33

Mine sounds the same.

I may mention it whenever I bring my car in to the dealer next, but I don't expect them to be able to do anything about it. Not that I'd necessarily want a tech taking apart my engine and putting it all back together again for something like that anyway... they'd probably make it worse. :P

I did drive in a friend's GT3 and his rattling was much less obvious than mine at all RPM and over all warm-up temperatures, so it definitely varies from car-to-car.

tasman

I heard the signal green ones rattle like hell!!!

bronson7

Just for the time being. What's your next project? Remember, it's only MONEY.

awew911

I have the same thing. Started within past few hundred miles. high frequency vibration in 1st or 2nd gear between 2 and 4 k. sounds like a heat shield vibrating. Definitely not internal to engine/gear. My lift will be here next week and ill put it up and look around. if i dont see anything extraordinary, ill bring it to dealer. i'll post what i find.

NYC_AREA_GT3

Yes when I say "floor pan" that's what I mean - the metal heat shield or pan or whatever that is under the engine but in front of the rear muffler is where it sounds like the vibration is emanating from. I'm taking my car in next Tues and will report back.