[wbdarby]

Hey guys,
I'm having a severe knock/ rub/ fluttering metal/ changing sound coming from my transmission housing. This has been going on for a long time now, say 3-4 months. It occurred overnight, and hasnt gotten any better or worse since day 1. Now, I say "knock" because that is the most prominent noise, but the overall sound is very compound - maybe 3 or 4 sounds together. The engine runs great, the tranny shifts perfectly and holds the power as normal all the way to 9k, the car is bone stock (MY2000) and a DD, all fluids are good and the car is kept in good condition. The sound is LOUD, but not always constant. My car is knocking ab 85% of the time, the other 15% it seems perfect - with no abnormal sounds at all. Think ball peen hammer popping the housing under the center console. The car has seen a mech and been on a lift. I trust this guy, and he couldnt figure it out, all he could tell me was "Your transmission is going out, you're going to have to replace it sometime. We're not sure exactly what is making the sound, but we had it on the lift and it's definitely coming from the tranny. I drove it (12 Miles) and it drives fine, so if you can live with the sound then I would. I dont expect to see you back for this within a years time." If I'm sitting at idle and the knock is a knockin' then I can do one thing to stop it... engage clutch, engage 1st gear, hold on brake, then start to slip the clutch almost all the way out, to where you would normally be rolling forward but youre braked this time. Right there, holding the clutch almost out, the sound will disappear. But clutch full out or full in, whether in gear or out and it will sound. One last observation I noticed a few nights ago.. On a very severe incline I was stopped behind another car at a stop sign. I was holding the car idle on the hill via clutch/ slight gas manipulation, no brake. I do this a lot, as I live in a hilly area, so I know what im doing there, but this particular uphill was very severe, the most radical angle in the area. Anyway, as im there chillin, the clutch seems to slip just a bit and a different, more forward in the car, rubbing sound occurred. This sound seemed "faster", if that makes sense. So, if anyone has any ideas or has run across this before I'd really appreciate your help. Ive been on S2ki for probably 7 years, reading and such, but this would be my first post. Ive done extensive searching for this specific issue on this forum and others and havent found an answer. Ive also seen a few "check this s2000 rattle" videos on YouTube and, again, havent heard/seen my issue before. I'd love to know if there is anything I can do for this other than wait until I need to replace the transmission, as my mechanic suggested. As I said, the car drives perfectly, but I'm just not sure I can take that sound anymore! It's really starting to take away from the enjoyment of the car...

Thanks in advance, let me know if theres any questions.

WD

[Reckon]

A video would help. Not sure what kind of sound as a knocking noise is not something I would expect out of the transmission. I thought perhaps the TCT was giving you the issue, but that noise is more of a card in the spokes noise. Have you had a valve adjustment recently? I know you think its the tranny, but noises carry deceivingly in the S.

[DFWs2k]

where are you located? i have an extra transmission I will let go for cheap if it will allow you enjoy your car again

[wbdarby]

DFWs2k, on 02 February 2012 - 09:50 AM, said:

where are you located? i have an extra transmission I will let go for cheap if it will allow you enjoy your car again

l
Im in Birmingham, AL. And that would probably be awesome!

I havent had a valve adjustment in awhile... this crossed my mind, but I think I let it go after the mech had it on the lift listening from underneath. You can not hear the issue from underhood or anywhere outside the car while its running, but it is very distinct inside the driver cabin - I cant figure that out. If you sick your head under and behind the right front wheel you can just barely hear the "knocking", but thats really the only place outside the car - this initially lead me to thinking about the tranny. Ok, im gonna go work on a video and try to post that up this morning.

Thanks -WD

[JohnsS2000]

there are motor mounts as well as transmission mounts that could be the cause. I would lean more towards a mount before looking to replace the tranny, especially if the shifts are good and smooth. You just posted up on this so I would wait for more replies as one of the long term owners that know the S really well, like Billman, can chime in.

Did you happen to lose an oil cap recently?? They get lodged in between the transmiision and the firewall

[Duo Maxwell]

Using my knowledge of transmissions and powertrains in general....pressing on the clutch will allow the transmission to spin down. At that point NOTHING in the transmission will be spinning, so nothing should really be making noise.


Start your car and when the noise is occurring, leave the car in neutral and press the clutch all the way in. Do not put it in gear, just clutch in for 10-15 seconds. Does the sound go away?

Could be something with the throwout bearing/pressure plate/clutch assembly.

Regards,
-Gabriel

[JackS]

Maybe a large hunk of slag from the transmission housing broke loose and is being tossed around within the case. Is there a tool that can inserted into the drain/fill holes to actually inspect the inside? If this were happening, I would think that there would be much smaller bits of metal being thrown off because of the collision with the rotating gears. What does your tranny oil look like when you change it.

[wbdarby]

JohnsS2000, on 02 February 2012 - 10:50 AM, said:

there are motor mounts as well as transmission mounts that could be the cause. I would lean more towards a mount before looking to replace the tranny, especially if the shifts are good and smooth. You just posted up on this so I would wait for more replies as one of the long term owners that know the S really well, like Billman, can chime in.

Did you happen to lose an oil cap recently?? They get lodged in between the transmiision and the firewall

Uh... Yeah... I did lose an oil cap right before this. That was my very first thought - I was told by Honda and my mech that wasnt the issue (but who knows if they looked well). Is there any way for me to search that area? That would be crazy, but it's a lot of noise, so I doubt it. Also, when this started I found the right motor mount damaged and had it replaced, to no avail. I suppose the tranny mounts could be an issue, but I had my mech check those too, so unless he really hates me they should be good. As for clutch in/ no gear at idle, it's still very noisey. I got a couple videos, hopefully you can get a better idea with these. After thinking about it, the "cards in spokes" isnt too far off from a partial part of the noise, just louder than say a bike with a playing card. I had a different mechanic change my tranny fluid just prior to this when I had it in for some rear shock work, everything seemed fine at the time, just dirty i suppose. I personally dont think its something in the tranny itself, just because it shifts perfectly, I dont feel anything blocking for messing with shifts ever, It just sounds like crap. Thanks to everyone for your help so far.

so... how do I upload these videos here?

[GoFaassttt]

Lost oil caps are known to make noise. Probably wedged between your tranny and tunnel.

[wbdarby]

I think this could be a combination of a stuck oil cap and the TCT. Ill try to work on the TCT this next week and see what happens.

[wbdarby]

Update: I replaced the tct with bill's unit and nothing changed at all. So, I'm assuming my tct was fine - MY00 @ 95k miles,, is that unusual? I left the new one in, might as well. Then, today, I had the trans dropped and found my old OIL CAP lodged on top. So, I fixed my rattle - that cap would have never come loose of its spot I don't think, so this was my only real option. Someone suggested it, and I thought about it but didnt really think it was possible. Well, that was annoying, but thanks for your help. Peace.

WD

This post has been edited by wbdarby: 23 February 2012 - 01:56 PM

[Billman250]

wow...awesome!

Lost oil cap has been a problem for years on the s2k. If it falls behind the engine, it will sit on top of the transmission and will never come out until you take it out. Causes a nasty knocking against the transmission tunnel. Glad you found it

[s2klariat]

Every time I read a thread like this it makes me paranoid to take my oil cap off, haha! A lot of work for such a split second mistake!