Rattle from inside the cabin

[Gonzo911]

There is nothing more frustrating than trying to find a rattle and this forum narrows it down to oh, about 100 possible causes! I am throwing this out there to see if you guys can help me get lucky.

03 996 Cab. 50k miles. 6-spd. The rattle sounds like something is loose (dash, door, top?) who knows where. I have tried pressing on all the dash components, cup holder, center console, speaker boxes, top, everything, but have been unable to isolate the location.

I don't hear it with the top up or windows down, but I am assuming that is because I simply can't hear it over the wind/road noise but I can't eliminate the rattle coming from the cab top or a loose window?

It is most noticible when I accelerate or hit the top of the rpm range for a gear, especially in the lower gears. If I am cruising in 3rd or 4th at 3000-3500 rpms the sound is not present, but if I punch the accelerator, I hear it again. I am assuming that the extra torque causes vibration that accentuates the sound.

I am open to all possiblities and will spend this weekend trying all of your suggestions. Thanks in advance.

[Gyorgy]

Hope this makes you fell better, I have a similar issue. Athough I have not been aware of it lately, maybe because I have the radio/music on. Mine sounds metallic, like a subdued loose change rattle in a tight space. I heard it when accelerating hard. Hope some other will chime in as to what could be done. Mine seems to come from the passanger side, BTW.

On a different note, I had the spoiler lubed due to some squeeking which I could only hear when I raised it when the car was stopped to see what it looks like. Anyway, it was done at Morong in Falmouth, ME and with a $50 off coupon they had sent me to b used for non-routine service, I ended up paying $6.91. I bet noone can top that!

Also, I have new winter tires on (Pirelli 240 Snowsports) and so far happy with the way they ride. Not noticebly noisier than the summer Contisports.

[logray]

Simple! Just remove your dash and then see if the noise is still there. Right?

In seriousness though, I find it helps to have someone else in the car to isolate these types of noises... have you tried that yet?

[Gonzo911]

I did, but the "spotter" was my wife who lost interest within 5 minutes. However, we concluded that the sound is definitely coming from the passenger side (similar sound as Gyorgy noted). I have it narrowed down to the passenger side door assembly, the speaker box on top of the dash or the passenger side airbag compartment. I am not going to mess with the airbag, but I am going to get to the others this week. Will post if I find anything. It is interesting that the sound comes and goes. I think that when the weather is warmer, the sound goes away. Good thing I live in AZ! Thanks.

[ltumacder]

There's a lot of fixes covered in the TSB's for convertible top noises. I implemented them one by one on my MY99 996 Cab until I was happy with the results.

[Gonzo911]

Thanks. It is definitely coming from inside the passenger side door. Must be from either the speaker box or window assembly. I will post what I find.

[mrhoff]

I had a similar, occasional tapping noise on the driver's side of my 996 Cabrio which was audible when I hit a bump with the top is down or the window open. The tapping noise stopped when I held the door slightly opened. It turned out to be the door lock mechanism tapping against the striker plate. It can be eliminated temporarily by spraying WD-40, silicone spray or a little oil on the striker plate.

[phillipj]

Okay this is could be the solution. There is something underneath your passenger seat that is rolling around. I had a similar situation in my 996 years ago. It drove me crazy. I had my wife ride along as well to try to discover the source. I couldn't figure out where it was coming from. The sound seemed to travel. First I thought it was coming from the back... Then the front..

I was just living with the rattle when one day (when I was detailing the car) I found a little screwdriver underneath the passesnger seat. I thought to myself.. This couldn't be the sound could it? Voila! Sound gone. 996 and 997 seats are famous for loosing and trapping things under the seats. Look under both seats meticulously.. You may just find the culprit. This topic has been covered before here and others have had the same solution as me.... Good luck!!

Edited November 29, 2011 by phillipj

[wyovino]

Check the spot near the visor where the cab top locks into the windshield frame. I had a rattle there. If you're lucky and that's the problem it's an easy fix. Pop out the plastic tab where the visor connects and tighten the two screws. I don't recall if you need an allen wrench or torqs screwdriver.

[pseasea]

I have found a rattle issue in the top. Where the cable attaches to the top frame with the spring, the riveted point has broken so the rivet and spring are loose in the channel and rattling around. The top is also loose and pulling up where the elastic piece pulls the top in so that it properly folds. I'm going to post a new item to see if anybody has ideas on how to reattach this spring to the frame and where it attaches.

[Gonzo911]

My problem was with the speaker box. I had a new sound system installed and they missed tightening the screws on the sub in the passenger door.

[kahdmus]

My 02 C4 Cab rattles a LOT imo. The plastic interior squeaks and the roof rattles. By comparison my 91 C2 cab is smooth and silent..build quality?