That mystery grinding noise typically after a clutch job
#43
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I really want to see a video of your noise to make sure its the same as mine.
What i know about mine:
Its the same deceleration from 4-3k rpm that you guys seem to indicate.
It started after my first clutch change. I took it to a shop, didn't perform the change myself. It was very obvious after the clutch change.
Since then:
I've rebuilt the engine
Swapped transmissions (M1 full syn in the tranny atm).
Upgraded to 1.8 Clutch/oem flywheel
Re-aligned my PPF (solved the issue for maybe one day, its back in just about full force again)
I suppose I could try rotating my driveshaft. It is possible that the shop put it on wrong and i just put it back on wrong after my swap (i marked it like you're suppose to, doesn't mean they did though). It seems fairly likely that this could be the problem.
My mechanic friend/fellow miata owner swears its just the sound of gears meshing together at certain RPMs, i dont buy it.
I'm starting to think u-joints. Have any of you swapped driveshafts yet? I might have missed this being mentioned when reading.
What i know about mine:
Its the same deceleration from 4-3k rpm that you guys seem to indicate.
It started after my first clutch change. I took it to a shop, didn't perform the change myself. It was very obvious after the clutch change.
Since then:
I've rebuilt the engine
Swapped transmissions (M1 full syn in the tranny atm).
Upgraded to 1.8 Clutch/oem flywheel
Re-aligned my PPF (solved the issue for maybe one day, its back in just about full force again)
I suppose I could try rotating my driveshaft. It is possible that the shop put it on wrong and i just put it back on wrong after my swap (i marked it like you're suppose to, doesn't mean they did though). It seems fairly likely that this could be the problem.
My mechanic friend/fellow miata owner swears its just the sound of gears meshing together at certain RPMs, i dont buy it.
I'm starting to think u-joints. Have any of you swapped driveshafts yet? I might have missed this being mentioned when reading.
#44
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I think it's safe to say u joints are out for us, sound can be produced in neutral. Plus I changed my driveshaft to the 1.8 one. You should try and see if you can make the sound in neutral to verify you're in the same boat as us. Rev up to like 3k in neutral and let off the gas quickly. Let us know.
#45
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I think it's safe to say u joints are out for us, sound can be produced in neutral. Plus I changed my driveshaft to the 1.8 one. You should try and see if you can make the sound in neutral to verify you're in the same boat as us. Rev up to like 3k in neutral and let off the gas quickly. Let us know.
#47
Cpt. Slow
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there is a bolt that bolts the tranny gasket (the thick metal plate) to the engine block, I left mine out after an engine rebuild (not on purpose) and it would vibrate against the block at certain rpm. any chance either of you left that bolt out? its around where the red circle, behind the flywheel obviously.
![Name: trannygasketbolt.jpg
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Size: 63.5 KB](https://www.miataturbo.net/attachments/general-miata-chat-9/210422d1501261068-mystery-grinding-noise-typically-after-clutch-job-trannygasketbolt.jpg)
#49
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there is a bolt that bolts the tranny gasket (the thick metal plate) to the engine block, I left mine out after an engine rebuild (not on purpose) and it would vibrate against the block at certain rpm. any chance either of you left that bolt out? its around where the red circle, behind the flywheel obviously.
![](http://i228.photobucket.com/albums/ee62/luc8421/trannygasketbolt.jpg)
![](http://i228.photobucket.com/albums/ee62/luc8421/trannygasketbolt.jpg)
#52
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Here is the one while driving, you can start to hear it around 13 seconds and really hear it around 24..
Just made this video this is in nuetral with the clutch pedal to the floor:
![vash](https://www.miataturbo.net/images/smilies/vash.gif)
It's the sounds that makes me punch infants![vash](https://www.miataturbo.net/images/smilies/vash.gif)
![vash](https://www.miataturbo.net/images/smilies/vash.gif)
I'm about 99.99999% percent sure I put that bolt in.. I have a pic somewhere maybe I will be able to check and see..
Just made this video this is in nuetral with the clutch pedal to the floor:
![vash](https://www.miataturbo.net/images/smilies/vash.gif)
![vash](https://www.miataturbo.net/images/smilies/vash.gif)
![vash](https://www.miataturbo.net/images/smilies/vash.gif)
![vash](https://www.miataturbo.net/images/smilies/vash.gif)
I'm about 99.99999% percent sure I put that bolt in.. I have a pic somewhere maybe I will be able to check and see..
#53
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
there is a bolt that bolts the tranny gasket (the thick metal plate) to the engine block, I left mine out after an engine rebuild (not on purpose) and it would vibrate against the block at certain rpm. any chance either of you left that bolt out? its around where the red circle, behind the flywheel obviously.
![](http://i228.photobucket.com/albums/ee62/luc8421/trannygasketbolt.jpg)
![](http://i228.photobucket.com/albums/ee62/luc8421/trannygasketbolt.jpg)
![Name: IMG_7275.jpg
Views: 3435
Size: 160.3 KB](https://www.miataturbo.net/attachments/general-miata-chat-9/210421d1501261068-mystery-grinding-noise-typically-after-clutch-job-img_7275.jpg)
#54
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You're sure it's not the heatshield rattling around?
In my Integra, I get a similar rattle. Something in the exhaust manifold B pipe was known to go bad. Replaced w/ headers and sound went away.
Obviously you're turbo, but maybe something along the same lines? Something loosey goosey?
Ever have anyone listen around the car for it? Screw driver to ear could maybe help isolate it?
In my Integra, I get a similar rattle. Something in the exhaust manifold B pipe was known to go bad. Replaced w/ headers and sound went away.
Obviously you're turbo, but maybe something along the same lines? Something loosey goosey?
Ever have anyone listen around the car for it? Screw driver to ear could maybe help isolate it?
#55
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The sound is still there with the turbo heat shield off, even the cat heat shield isn't on because I thought it might have been the cause. I have tried listening with a screw driver and cant hear any single spot it is coming from. It's so loud that it resonates throughout the entire engine bay, but it seems to be the loudest behind the engine were the block and tranny come together, on the passenger side.
#56
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I've got this same exact sound coming from my car as well. Grinding/rattling noise under deceleration. Thought maybe the transmission was on it's way out, but it shifts fine and runs great, so can't be that. This started after I changed the engine in the car earlier this year. Really interested to see if someone on here comes up with a solution.
nicacus: Those videos confirm that the noise I am hearing is exactly what you are experiencing. So we're in the same boat.
nicacus: Those videos confirm that the noise I am hearing is exactly what you are experiencing. So we're in the same boat.
#58
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I got the car up on stands and tied the throttle to hold it at 4000RPM.
While I was under the car it seemed like the buzzing sound was coming from the cat, I'm going to see if I can hear the noise with the cat removed once the car cools down.
I'll have a test pipe here on friday, hopefully that will fix it if the cat is the culprit
While I was under the car it seemed like the buzzing sound was coming from the cat, I'm going to see if I can hear the noise with the cat removed once the car cools down.
I'll have a test pipe here on friday, hopefully that will fix it if the cat is the culprit
#59
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I have a noise on de-acceleration, doesn't like either of the videos I wonder....... also I haven't checked the positioning of the PPF yet but, however before I replaced the clutch I had it the flywheel resurfaced would that effect anything?