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Discussion Starter #1
Lately I've been noticing a slight rattle/whirring/grinding sound at partial throttle mostly on the highway in 6th. If you let off the gas completely it goes away and at more than 50% throttle it goes away as well. You can hear it when you're just getting on the gas a little. It kind of sounds like a throw out bearing went out but it doesn't make any sound idling with the clutch in or out.

Anyone else experience this? My car is stock powertrain wise so no supercharger jokes :)
 

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Go over the rear of the car with a fine toothed comb...err, wrench. Look for loose fasteners and even push up on undertray and diffuser panels to see if there is any play. And yes, my first thought was "oh that's the SC sound", but then I looked at the year. :D
 

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Lately I've been noticing a slight rattle/whirring/grinding sound at partial throttle mostly on the highway in 6th. If you let off the gas completely it goes away and at more than 50% throttle it goes away as well. You can hear it when you're just getting on the gas a little. It kind of sounds like a throw out bearing went out but it doesn't make any sound idling with the clutch in or out.

Anyone else experience this? My car is stock powertrain wise so no supercharger jokes :)
I have the same thing but from the front of my car. The sound goes away when I slightly am on the brakes but rolling around the parking lot, it sounds loud.
 

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I've got the same thing too. Actually was thinking about taking to the dealer to see if they could figure out what it was. Doesn't come on under full throttle just part throttle. Hopefully someone has already figured this out and will save me a dealer trip.
 

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Joseph,
Did you check the heating shield is not rubbing anywhere against the diffuser? Also that all the under tray bolts are tight? I had something similar was just the heating shield for the exhaust was vibrating against the rear diffuser. And another time on the track but was a bold lose vibrating on the under tray.
 

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My car makes a soft whirring/whining sound only at a very specific throttle point. Not a specific throttle point as far as the amount of pedal travel, but rather whatever specific throttle point is required to put the car in a no load condition. That is to say: not accellerating, or even holding speed, and not engine braking either. Jut that nuetral point where the transmission is not loaded with torque in from either end.

When this condition is reached, the soft whirring/whinning is evident. It sort of sounds like a supercharger spinning, but not as loud. I believe it is gear lash in the transmission, and is heard only when the gear teeth are not firmly pressed against each other by torque from one end or the other. I strongly suspect that most cars have this noise, but just never notice it.

xtn
 

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Hey guys, I think this is the same noise I posted about a while back.

I looked at the heat shields very carefully--indeed one rivet was loose and very rattly, I'm sure. But that wasn't it. I also bent the heat shield slightly so that when I'd rap on the exhaust with my hand, there was no buzzing sound. When I installed my HIDs, I secured nearly everything in the front half of the car that wasn't totally constrained. No luck.

Sandsmuseum said he thought it might be something in the shifter linkage. He suggested checking where the two shifter cables exit into the engine bay from the passenger floor. So I put strips of closed-cell foam tape to cushion anything with any chance of rattling. Still no dice.

My next step is to remove the shifter console and push the linkage around while driving, just to see if anything changes. Sandsmuseum said that after bolstering up his shifter linkage (notes on his site), he thought the noise lessened a bit, but wasn't totally sure as I recall. He mentioned it's no longer present on his 08 240, btw.

If it's the same noise as mine, it sounds vaguely like backlash would in the transmission, but I doubt it's the transmission given it's a toyota unit and they're used in many other cars.

Sometimes I forget about it, but when I hear it, it really detracts from the driving experience since it makes the car feel not so solid.
 

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Discussion Starter #8
I'll check the diffuser and underpanel tonight to make sure nothing is loose but it sounds like something more mechanical rather than just a loose piece rattling around. My Miata's throwout bearing is going out and it sounds very close to the same thing. The car performs perfectly and shifter/transmission is fine, just a bit annoying and wanted to see if anyone else had the same issue.
 

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I believe this is a common sound to most early cars. My 2005 makes it, as well. Just as described: rattle at neutral throttle.

I believe the consensus has been that it's related to the shifter cables. When the transmission isn't under torque, they rattle, I suspect at or near the transmission end. I can modulate the sound a bit by pushing firmly on the stick when the noise is occurring, but I don't recommend doing this for too long; I don't think it's terribly good for the transmission.

There have been reports of solutions to this problem. I don't know what the solution is, but I'd love to know. Anyone want to try being more successful at searching the archives than I?

- Geoff
 

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I didn't describe it as a rattle, but the op did use that word. I don't know what kind of sound is a rattle/whirring? A rattle and a whir are different sounds to me. Don't know if we're trying to describe the same thing or not.
 

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I didn't describe it as a rattle, but the op did use that word. I don't know what kind of sound is a rattle/whirring? A rattle and a whir are different sounds to me. Don't know if we're trying to describe the same thing or not.

you should prolly try to use your mouth to replicate the sounds then record it on your computer and put it on here.... seems like the best option rotfl rotfl
 

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you should prolly try to use your mouth to replicate the sounds then record it on your computer and put it on here.... seems like the best option rotfl rotfl
<object width="425" height="355"><param name="movie" value="http://www.youtube.com/v/NcAYHq9tduk&hl=en"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/NcAYHq9tduk&hl=en" type="application/x-shockwave-flash" wmode="transparent" width="425" height="355"></embed></object>
 

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My car makes a soft whirring/whining sound only at a very specific throttle point. Not a specific throttle point as far as the amount of pedal travel, but rather whatever specific throttle point is required to put the car in a no load condition. That is to say: not accellerating, or even holding speed, and not engine braking either. Jut that nuetral point where the transmission is not loaded with torque in from either end.

When this condition is reached, the soft whirring/whinning is evident. It sort of sounds like a supercharger spinning, but not as loud. I believe it is gear lash in the transmission, and is heard only when the gear teeth are not firmly pressed against each other by torque from one end or the other. I strongly suspect that most cars have this noise, but just never notice it.

xtn
If it's this I think every manual transmission does this.
 

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If it's what I think we're talking about, in lieu of fortifying the center console with Dynamat, I had been inclined to get a leather-covered one from the trim shop to lessen the din.
 

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Discussion Starter #15
If it's this I think every manual transmission does this.
None of the 4 other manual transmission cars I've ever owned did this. None of them were mid engine either though (I guess the RX-8 and S2000 don't technically count as mid engine)
 

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None of the 4 other manual transmission cars I've ever owned did this. None of them were mid engine either though (I guess the RX-8 and S2000 don't technically count as mid engine)
Those cars had much more sound deadening and attention to NVH than any Elise will probably ever have.
 
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