klemen123

Recently car has developed a vibrating-knocking-rattling sound. I pulled with 1st gear to around 8k rpm and shifted to second and this is what i have now .
I feel tapping vibration on shifter and vibration on clutch pedal. Engine sounds normal and there is no knocking coming from the engine bay.

The car is year 2000 with 105000miles on it.
The engine sounds fine.
Shifting is normal without any grinding, even when shifting fast.
The clutch was replaced about 12000miles ago, with genuine Honda disc and RPC stage 1 pressure plate, throwout bearing. (It worked perfectly fine until now)
The flywheel and pilot bearing wasn't replaced back then (they seemed fine).

Simptoms:
-Weird rattle(?) noise when accelerating, starting at about 2500rpm, it doesn't matter if the clutch pedal is pressed in (maybe its little louder if the clutch is engaged) or out or if the car is moving, or in which gear I am(in second gear its a little louder). (as seen in the video)
-Vibrations on clutch pedal.
-Vibrations and tapping feel on the sift knob.
-Noise is very audible in the car where the shifter is, outside the car you can barely hear a thing. ( may be because of that loud exhaust)
-When at stop in first gear, clutch pedal pressed in and giving it some gas, the car wants to slowly launch forward (well I'm frankly not 100% sure about that, I thought the car made this yesterday, but today, when I wanted to do it again, I didn't feel it).
-I think there was a bit of clutch buzz at the end of the video while decelerating, that wasnt there before the problem started.

I went through hundreds of S2ki threads and YT videos but I just can't find even a similar match :/ since we have just about 20 of the S2000's in our country (Slovenia), even our best Honda mechanics dont have a lot of experiences with this car and I already had some really bad experiences with them because of that (broken knock sensor since they didnt know you need to unplug it before tilting the engine). So I would like to know some basic guidelines before turning to them for help

One more thing, when i bought the car it had a bad second gear grind issue and after several oil changes i stayed with motul gear 300 75w90 gl4 /5 rated transmission fluid wich solved the grinding.

Thank you all, and sorry for any grammar mistakes

Kazuken

What are the conditions of your Motor and Transmission mounts?

klemen123

did not lift the car yet but on the engine left and right one look clean and dry :/

klemen123

here is the hd version of the video for better audio and video

jyeung528

i don't think you're supposed to use 90w oil in the transmission. the amsoil mtf is a 30w oil and i would also imagine honda mtf is close to 30w as well.

looks like you're going to have to open this transmission up and inspect the parts. let us know what you find.

windhund116

Maybe a broken clutch pressure plate or disc. Were they ever replaced?

Inspect the driveshaft and axles for damage or interference. As said, may need to drop the tranny.

Sorry.

Mullallyman

Yes I've heard people using 80w oil quite a bit in our transmission. I wouldn't expect that to be it.

slavic

klemen123, what kind of work did the mechanics attempt when they broke your knock sensor? Engine or transmission?

klemen123

Mechanic replaced clutch disc with geniune honda disc. Pressure plate and throwout bearing remained untouched (RPC stage1 parts). I replaced the disc with geniune disc because of clutch buzz. clutch replacement resulted in broken knock sensor which was replaced.

klemen123

Quick update!

Lifted the car on 4 stands. Checked all motor tranny and diff mounts, they are perfectly fine, no cracks no excessive movement. I regreased shifter and replaced the spring and plastic ball at the bottom, now there is no high pitch rattle at the top of the shifter, yust tapping and knocking felt through the shifter. Rattle/vibration/knocking can still be heard between the engine and tranny area, but when i listen under the car i can barely hear anything. Started the car in the air went through all gears, shifts prefectly fine except the vibration on clutch pedal while engaging and dissengaging. The sound is more pronounced when the engine or tranny is on load.

Sound of knocking/ratteling also happens just when the clutch starts grabbing and slightly dissapears when it grabs (can still be heard clearly).
Also changed diff oil to check the magnet and there wasnt any excessive metal shavings. Changed engine oil, filter, the engine runs very well and there is no ticking and knocking in the engine bay or even under the engine.

Then when i was regreasing clutch fork where the slave cylinder pushes i thought can start the engine and try to listen in the for area for any noise with the rubber dust protector off. There is almost no knocking sound heard except if i touch the clutch fokr i can feel vibration and knocking through it but when i push it a litthe torwoards the slave cylinder the vibration on fork stops but it still can be felt if i put my hand on the clutch case. One more thing i noticed that i think the pressure plate is wabbeling nad not spinning straight, but that can just be the uneven dust on the plate that creates a illusion :/.

Went to the mechanic and we will remove the transmission and inspect the clutch and flywheel.