Renzsport

Has anyone experienced a quiet rattle/vibration type noise from the engine?

Occurs most commonly while in motion, but doesn't take too much speed to get drowned out by wind noise. Almost sounds like a tinny sound. The best description I can give is when you're stopped at the lights and a crappy minivan pulls up with a noisy ac compressor/power steering pump. Except the occurence in my case is different, more like a rattle I'd say.
Loudest just after engaging clutch when getting going (~1500rpm) but sporadically up to 3500rpm anyways. And also when downshifting and the revs end up at 3000rpm. But difficult to reproduce except when first getting going.
Indeed, sporadic and quiet.

If I've lost you, fair enough. It's a strange one. Had a tech ride along for a bit and he couldn't say for sure so it's going in later this week to get a better look.

ffwd

my '12 997.2 C4 also sometimes has a tinny rattle/vibration from the rear drivetrain or engine compartment while (and/or immediately after) the clutch is engaging, ( I think for gears 1, 2, 3) especially if I have already advanced the throttle and am a little slow/late on engaging the clutch so there are more engine revs than would be ideal for that shift but then bogs down a little bit into the next gear. It sounds like maybe a heat shield or the like vibrating, but could be something more mechanically involved in the clutch or transmission. Sometimes I have wondered if it is engine knock when it occurs at low rpm under load following clutch engagement. If you figure out yours, I'd be interested to hear what it is.

utkinpol

Only rattle to worry about is chain, it usually happens at startup until chain tensioner gets filled with oil. When chain rattles at idle it is not good at all.

niner niner seven

I believe I have the same issue that you speak of and I have posted here to find out why. My sound only occurs at 1200 rpms post 1st gear engaged. I have recorded the sound. What year is your gen1? Mine is 2006 4S.

You will have to search threads started by me or search " "Crank" sound after engaging 1st gear " for my post and member responses. My weblink address remains a constant forums.rennlist.com so i cannot copy the link directly for you to click on. Let me know what you think.

jason74

I have a tinny type noise that occurs under hard acceleration between 4-5k rpm. I am pretty sure mine is a heat shield under the bumper. I've been trying to gently move/ bend different sections at a time and it does improve. I could duplicate the pitch of the noise by banging on the bumper skin in different sections.

Renzsport

hmm niner yours is a bit different in that it is only at the one precise time/rpm range. I would think it's exhaust related?
Mine seems to happen intermittently throughout the rev range (certainly up to 3000+rpm). My truck has a heat shield vibration but again it's only at a specific rpm, which makes me think this sound on my 911 is slightly different. Anyways, taking it in tomorrow and they'll have a good look at it, I hope they come up with something.
Mines a 2007.

niner niner seven

Jason, how many miles are on the car? I ask bcuz at 60k the heat sheilds will be removed anyways to get to the plug change. So you might wait until these are removed, placed back on and determine if sound is still there.

niner niner seven

Let us know what the verdict is/was.

All: I was in the car tonight. The sound occurs every time I pass thru 1200 rpms in first. This has nothing to do with the changing of gears as the car is already engaged. So everytime it passes thru 1200 = sound. Moreover its more pronounced and louder when sport mode is on. Any ideas?

Renzsport

ok so my noise is attributable to some sort of weakened/bent/broken muffler support tabs. I didn't get to speak with the tech as he left before I got to the shop so I can't explain it much better. The guys at the front apparently didn't talk to him either, just going off his chicken scratch on the ticket.
He couldn't fix it properly because it's stainless steel and he didn't have the correct welder, but he put a couple spot welds to shore it up. Full fix would be to have them welded properly/fully.
I have no idea how this could've happened... But I didn't get charged at least.
cars got ~24000 miles (just under 40000km)

So Niner I think your issue is different, I would think something internal in your exhaust system?

niner niner seven

Yes, no clue. Thanks for following-up, did your noise stop ?

Renzsport

its reduced. I'll have to get it completely welded.