I posted the following query on S2000 Talk and didn't get much response. Anybody of our seasoned souls have an idea? I'm pretty sure that it's NOT the rear suspension b/c the noise is more of a 'shaking' than a 'thumping'. I didn't notice it in warmer 'top down' weather, so I wondered if there could be anything that needs to be tightened with the top mechanism or glass rear window

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When I go over rough road or sharp pavement cracks, there is a new noise that seems to emanate from behind the seats. It doesn't seem to be a loose seat or seatbelt; doesn't seem to be the frame for the top; and it's not a loose mini-spare tire. The rear spring spacers have been removed.

Any other ideas? Is there any other top mechanism that could be rattling/ thumping? I checked the various FAQ's and did not find any help. My 03 is a creampuff with 17k miles....just purchased over the summer....so this is my first winter (top up mostly here in Peeay

 

Shaking-alignment, or tire balance.

 

CV joint....do a search on it or PM xviper

 

Jerry -

If I understand what you are describing I would bet it is a weather related problem. Something somewhere is being affected by the cold weather. Some piece of plastic or metal is shrinking or expanding and causing this.

 

Thanks for these ideas. Would the CV joint be a problem at such low mileage? I did have my accident over the summer...damage at the front of the car....off center

 

Jerry, I am not sure, but your description of your problem just seemed to fit the description I recall for CV joint problems....Xviper is probably your best bet.

 

Jerry, it is these times that I wish I lived near you so I could hear and feel what you are hearing and feeling.
However, here are some thoughts:
1. It could be your top latch. These have been known to rattle when bounced. Try this -- Get some duct tape or electrical tape and tape both latches (closed) so they will not move in any way. If the noised stops, you have your answer.
2. It could be the cooler temps is making your top move around more than normal when you hit a bump. Go for a drive with someone who can reach around and hole the top down with some moderate pressure. Go over stuff that normally makes the noise happen.
3. Another weird thing that has be posted here -- Wheel weights. We have stick on wheel weights. These can become partially detached when the "stickum" loses some adhesion from road grime and washing, etc. If you hit a bump in just the right way, the weight can flip up and down. However, this would not be a consistent occurance because the weight must be in a precise orientation for a bump to cause this oscillation. Reach through each wheel's spokes and give each wheel weight a gentle tug to see if any are lose. If they wiggle in your fingers, you may also have another answer. You'll need to re-stick them or get new weights.
4. Each suspension spring sits on "perches" that are made of rubber like material. If these perches shift or become a bit dry, they can possibly shrink. When you hit a bump, there could be enough slop in the spring movement to cause a noise. Whether or not it can make a noise as what you witness is yet to be determined.
5. To test the CV issue for vibration, you must accelerate briskly. The typical CV problem will manifest itself in a noticeable vibration mainly upon acceleration. If it does this, then you may have pitted CVs. Honda has a TSB on this and you may get a free fix.
6. Each shock has a metal sleeve to protect the rod that goes in and out. There isn't much clearance between the sleeve that the main shock body. When cold, it's possible that a bump could result in the sleeve coming into contact with the shock body. The sleeve can vibrate much like the metal strip on a "Jew's Harp". Go and give each sleeve a good flick with your hand and see if there is noise and if the noise is familiar.
7. You didn't say if this happens when the top is up or down, thus you can ignore #1 and #2 if the top is up and latched. The top tray, rear vertical liner, sides and front wall of the soft top well are metallic and are held in place with a series of "push pin" type fasteners. Any of these missing? These pieces can also resonate if you go over a bump. Suggestion -- put something heavy-ish back there to hold those pieces firm. Something like bean bags or sacs of rice.
8. I know you said you checked the spare tire tie down, but you should have a good look in there to see if some object hasn't come loose and has fallen into or under the spare.
9. Each wheel ABS sensor has a cable that is attached via a bracket and bolt. Check them all to see if any of these are loose or missing.
10. Check the stuff under the car near the rear diff - EVAP cannister tie down, diff mounts (leaking?).
11. Under the car, you have a conduit that runs the length of the car on the left side. This is where the fuel lines, electrical cables run. There is a plastic cover over this conduit. The cold can cause this cover to shrink and sometimes can cause a "buzzing" noise on bumps. You'd have to stick little wedges of cardboard to hold this cover firm all along its length.
12. Of course, there's the "age old" exhaust system sounds when heat shields and muffler internals age and get a bit loose. Go back to each exhaust tip and with the palm of your hand, give each one a good slap. Any familiar noise?

Ordinarily, I don't do "noise" threads much anymore because of the nearly countless possibilities, but for a friend ............................................

 

When you stick dead mobsters in your trunk, you are supposed to make sure they really are all the way dead.

 

Great post, Dave...I'm sure other members will benefit from this one, too. Thanks!

 

^ I agree and I'm printing it out because I had a thumping noise that went away after a few minutes and miles but it was bugging the crap out of me until it stopped on its own. Thanks, Dave and others.