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I've been noticing a slight rhythmic knocking noise at idle with the transmission in neutral after the car is fully warmed up and has been driven a while. I can also feel it in the gearshift knob.

While idling at a stop in neutral the noise goes away if I depress the clutch and comes back if I let the clutch out. The noise also goes away if I bring the rpms up slightly. Can't really hear anything out side the car and the motor appears to be very quiet. Only hear this inside the car with the windows up.

I know there is a TSB for the stretchy belt causing idle knocks and ticks but that TSB has been done and it made no difference. What's weird is that some days its there and others it isn't. The other thing I was thinking might be the transmission input shaft bearing as pushing the clutch in would stop that from turning and I understand those have been problematic in more ways than one.

I'm just wondering if this is typical of these cars. Mine only has 11K on it and I am an older conservative driver so it hasn't been beat on.

Anyone else notice this before I ask my dealer and they tell me they can't hear it or it's normal?
 

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It's the throwout bearing or something that rides on it, like a stuck diaphragm finger; indicated by the fact it goes away when the clutch goes in and returns when you let it out. Could also be a bagged pilot bearing but, that's not too likely. That's it, you'll have to trade it in for an auto now :smile:
 

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That's it, you'll have to trade it in for an auto now :smile:
I probably would have got the auto if it was available with the Brembo package in 12.

Went out and drove it and listened again. Now I'm wondering if it may be an exhaust knock. It sure sounds just like the thumping I hear out of my Borla S types at idle when I listen at the tip. I have stuck my head under the car everywhere and it is very smooth and quiet. Inside the car if I listen around the floor boards or put my ear down to the gear shift lever it is very quiet. I just hear it when I am sitting up. Cabin resonance from the Borlas? But that doesn't explain why it seems to go away (actually just lessen) when I push the clutch in, unless that is changing the engine loading just enough to affect the sound a bit. And barely raising the rpms makes it go away completely and not just increase in frequency. It's all rather weird.
 

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I hear you...my last car was a BBP '12. I wasn't going to sacrifice all the performance bits to get the auto and no select shift. My '14 rules that way.

Well, if you think it's exhaust, time to get under there and start looking for witness marks. When you clutch in the engine and trans do move slightly on their mounts and that'll slightly move the exhaust. Common tap points are the over axle pipe on the DS hitting the panhard support, The H pipe clamps hitting the floor due to being in upside down. Just go in sytematically. If you don't have a lift or jackstands, go to a jiffy lube and ask them to let you in the pit to look around. They might let you, especially if you change the oil while you're at it.
 
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