Knocking sound at idle from transmission, vid inside

[fbody83]

I finished putting a new motor in my car the other month and I've been working out a few kinks here and there. One thing that bothers me is this knocking noise at idle coming from the transmission. This was not present when I had the stock motor in the car. I took the dust cover off and inspected the throwout bearing while the car was running and it's not spinning so it's not the problem. I also don't see anything moving around, such as the bearing bouncing around or the fork knocking on something. When I push the clutch in (ALL the way), the noise goes away. Pushing the clutch in half way does not help. Check out the video below to hear it. When I put the camera down for a second time, I get in the car and push the clutch in a few times. You'll see that the noise goes away.

00091.MTS - YouTube

Any thoughts on this? The cams in the car make the motor shake around a little so I'm wondering if this has something to do with it. If the car idles at 1000 rpm there is no noise. Once it drops lower to around 750 - 800 I start hearing it.

 

[TRBO VNM]

Definitely doesn't sound like TOB or even the ring from the flywheel loosening up. What clutch do you have and how old/miles is it?

 

[fbody83]

Definitely doesn't sound like TOB or even the ring from the flywheel loosening up. What clutch do you have and how old/miles is it?

It's a spec 3+ and it's 2 years old with about 6000 miles on it. I had it in the car prior to my new motor and this sound wasn't present. Everything with the install went fine so I'm lost as to what this could be.

 

[fbody83]

Any other ideas on this? I could pull the transmission but I don't think I'll find anything if I do. I guess that's really my only choice from here.

 

[MrJohnny]

I have the same noise just not as prevelent.

What is i!!?

 

[Jefe]

Do you hear it while under load/driving? If so does it increase in speed or volume?

I noticed 2-4 drops of liquid between the midpipe tubes where the trans is, not sure if its related. Could just be the ac dripping onto the headers and running down the pipes

 

[Davey07]

I finished putting a new motor in my car the other month and I've been working out a few kinks here and there. One thing that bothers me is this knocking noise at idle coming from the transmission. This was not present when I had the stock motor in the car. I took the dust cover off and inspected the throwout bearing while the car was running and it's not spinning so it's not the problem. I also don't see anything moving around, such as the bearing bouncing around or the fork knocking on something. When I push the clutch in (ALL the way), the noise goes away. Pushing the clutch in half way does not help. Check out the video below to hear it. When I put the camera down for a second time, I get in the car and push the clutch in a few times. You'll see that the noise goes away.

00091.MTS - YouTube

Any thoughts on this? The cams in the car make the motor shake around a little so I'm wondering if this has something to do with it. If the car idles at 1000 rpm there is no noise. Once it drops lower to around 750 - 800 I start hearing it.[/QUOTE


This is 100 percent the exact same thing my car does, i turn on the ac and it goes away..I also have a spec 3 plus clutch and fidanza flywheel.. i just pulled the tranny and replaced the sleeve, tob, and found the ring gear on flywheel was loose. put eveyrhting back together , sounds better, but noise still there..

I'm coming to the conclusion that spec clutches are terrible.. coming the winter I'm ullng the the trans again, and putting in somehting different..

 

[Davey07]

Definitely doesn't sound like TOB or even the ring from the flywheel loosening up. What clutch do you have and how old/miles is it?

is the ring gear on the flywheel lossening up a common problem? mine was loose, so i put loctite and cranked down the bolts as tight as i could..

 

[Slobanator]

Find anything out?? Installed my spec stage 5 and fidanza flywheel and have the exact same noise.

 

[Nick Denny]

Did anyone having this problem figure it out? I'm having the same issue. New centerforce dual friction clutch installed less than 3k miles ago. I pulled the clutch and trans and had both inspected by a reputable shop and they said everything was ok. I replaced the throwout bearing when I put it all back in and it's making the same noise/vibrations. Also it feels like it's binding in reverse. 03 cobra with simple bolt ons. I've searched high and low and keep coming up empty handed. Sorry to bring up an old post. Thanks in advance.

 

[Ourobos]

Sounds more like an external vibration to me..

 

[MG0h3]

Sounds more like an external vibration to me..

Sounds like the headers are bouncing off something...a arm, k member, floorpan.

 

[Blitz34]

Please tell me someone figured this noise out. I have the same issue. I notice it when I put the car in reverse and let the rpms drop low. Its a knocking noise definitely related to clutch and trans. Its like if I pop the clutch and don't give it gas it rattles almost. Only way I can describe it is a disengage/re-engage in gear causes a shudder or rattle and slowly rolling in reverse mine would really make the noise. It sounds just like this video but I can make one too. What is everyone finding? I'm about to sell the car and want to either be able to say it needs a clutch, tob, or something needs to be tightened.

 

[atlas12b]

So my problem sounds kinda similar to yours. These are my two videos...
https://www.youtube.com/watch?v=dUWyphSGNEU
https://www.youtube.com/watch?v=kyBN-4u0Je4

So the sound goes away when the clutch is pressed in and comes back when released. It is also way louder when under load (in gear, moving forward, foot on gas) and then "goes away" pretty much when you let off the gas.
I don't know. I took it to a shop recently they said the throw out bearing was all messed up. They also said the TOB retaining sleeve was not damaged. So they replaced the throwout bearing and the sound was still there so they took another look and now are saying the sound is coming from the inside of the transmission. So I'm in a pickle I really don't want to pay for a new transmission and I also don't think it's a header knocking into something.

 

[Blitz34]

I'm not sure if this helps but I found this when checking under the inspection plate. Should it move this way?

http://s180.photobucket.com/user/DJPUNK34/media/Car/17E6E548-94D0-4EB2-962D-2C04256B2978.mp4.html

 

[Blitz34]

http://s180.photobucket.com/user/DJPUNK34/media/Car/17E6E548-94D0-4EB2-962D-2C04256B2978.mp4.html

 

[speedoflife]

ATTENTION:
I can't find it right now (sorry busy guys) but there is a thread somewhere talking about this video (I think his username might even be the same here as on youtube). I think it might be the answer to what is causing this noise. Sorry I can't be of more help but I've seen this topic discussed at length before

https://m.youtube.com/watch?v=xuvBC9-0JqA

 

[Shadow Grey 03]

Anyone check their weight on the clutch fork?

 

[WHITESTRIPES]

Definitely reminds me of my broken throw out bearing retainer sleeve. It would knock until the clutch pedal was completely pressed down. It could be anything but you won't know until you get in there.

 

[pipejob1]

My Mach1 with a T56 does the same thing press the clutch in and it goes away. Let it out and sounds like its rattling