Constant chirping Noise (literally like a cricket) when off the clutch

Car: 2003 C4S. 62K miles. P revious owner installed aftermarket clutch. When I drive around town, there is a constant chirping when my foot is completely off the clutch. The second I lightly rest my foot back on the clutch it goes away. It doesn't seem to be coming from a specific side. I've seen a couple other threads here but nothing that describes this exactly. Any ideas? I plan to revert the clutch back to stock and wondering what other parts I'll need.

Could be the throw-out bearing. Slight pressure on it by your foot resting on the clutch pedal takes up any play and silences the bearing. Just a thought, though. Or your dmf is causing it but I'd think it would only doing that at idle revs. Or something else entirely: your aos is broken, full intake vacuum is pulled from the crankcase and air is sucked in past the crank seal. Putting your foot on the clutch may move the crank ever so slightly that the noise dissappears. That noise would be more of a whistle than a cricket

My car actually does this, and someone else reported it too. I think there is some play right there at the clutch pedal. I haven�t had time to mess with it.

Quotes source post: 19661493

Thanks, I'm really hoping its the throw out bearing.

Quotes source post: 19662778

Not sure how it could be the TOB...? As the throw out bearing (&pilot shaft bearing) is/are only in play when the clutch is pushed in. Throw out bearing is just seating there on the shaft sleeve not moving till the clutch is pushed in. Then throw out bearing presses in the fingers of the pressure plate then must spin at crank speed, releasing the tranny input shaft and clutch disc from spinning allowing the crank to spin free on the pilot shaft bearing and throw out bearing. One thing it could be, is if the clutch pivot/linkage is screwed up and its constantly making tob slightly hit the pressure plate fingers slightly, making your 'chirping'. Or maybe the clutch slave/clutch master fluid is contaminated and 'boiling/expanding' causing the bearing to be slightly pushed into the pressure plate to make the chirping and when you press on clutch it fully hits the fingers of pressure plate stopping the noise..? Easy enough to try to flush/bleed the slave. Whatever is causing the noise, if you're sure that depressing the clutch stops the noise, then your problem must be in there somewhere. Suppose it could even be something loose in the DMF that tightens up when clutch is pushed, or even the tranny input shaft bearing. does the chirping increase/decrease with engine rpm..?... Just thinking out loud bout your problem and trying to help... jmo

The throw out bearing is always in contact with the pressure plate. Think for a moment about how much pressure it takes to seat the clutch slave cylinder in the bellhousing when you have to remove the slave. There is no spring in the system to pull the pivot arm back away from the pressure plate fingers. The bearings in the throw out bearing are dry and will fail soon. The light pressure from the slave cylinder is causing the bearing to sing/chirp as it rotates. When you push in the clutch - more pressure is applied and all the ***** start doing their job, and the sound goes away (for now). -Tom 2003 C2 1997 M3 BMW CCA clubracer that had a throwout bearing doing the same thing...

Quotes source post: 19663349

This ^ is incorrect. TOB only touches the pressure plate when clutch is engaged. Thats why you should never keep your foot even lightly on the clutch when driving. When doing engine/tranny swaps one of the most important things to set up is a 1/8-1/16" gap between PP and TOB.

allcool - I respectfully disagree. Again - try installing the clutch slave cylinder in the bellhousing - think how hard you have to push to overcome the internal spring of the slave and the fluid pressure. There is no return spring on the clutch release lever to pull it away from the pressure plate. The TOB and pressure plate are in constant contact - light contact, but constant contact. Unless the pressure plate fingers are bent causing the TOB to knock back away from the pressure plate (similar to brake pad knockback when you have a warped brake rotor or worn wheel bearings). Prior to hydraulic clutch activation - when the pedal was fully manual - yes, there was a spring attached to the clutch release lever to pull it away and return the clutch pedal to the upper position. As to adjusting the setup on a engine/tranny swap vehicle - you employ adjustable pivot points for the clutch release lever - the factory 996 does not have an adjustable pivot point for the clutch release lever. If you don't believe me - drill a hole in the housing - use an inspection camera and verify it in action. -Tom

says op doesn't have stock clutch. Tranny will need to be pulled to fix either way. If u had a shop put in an aftermarket clutch I would just take it back to them.

I would certainly not be pulling the trans or replacing the clutch as a next step. Like I said, the chipping noise I have on my car (occasionally, rarely) is actually coming from the clutch pedal itself. I would start there - OP - get under the dash and look and listen to see if it�s coming from the pedal, or if the noise is being transmitted from the clutch to the pedal. What�s possibly happening is that a throw out bearing or pressure plate is not 100% perfectly round, and that back and forth cricket noise (squeak) is moving the clutch pedal actuator back and forth. If that�s the case, maybe even some lubricant by the clutch pedal connections could resolve the issue. Are there not any pads, shims, or adjustments for play anywhere by the clutch pedal? There�s a helper spring, and switch there as well that could be causing the noise.

Any insight into location where the noise seems to be emanating from? regardless, I suggest you check all the spark plugs are properly torqued. I had a similar little noise in an M96 and one of the plugs had worked its way loose just enough to allow for a leak that sounded much like you describe. good luck in any case!

Quotes source post: 19665798

If op can't decipher if noise is coming from pedal or trans housing than there are other things he should prob be worrying about...like maybe getting hearing checked or just general mental state if coming from trans very likely trans will be pulled, hence my rec to take back to shop. Or if op would like to provide more info that'd be helpful too

Quotes source post: 19665901

OP should be able to check it with the car cold and not running. Just have someone (kid, friend, spouse) repeatedly press the clutch in/out while they are beside/behind the car listening for the location. Even if OP doesn't know the name of the part where the sound is coming from (or general area), they can take a pic and circle and write, "Sound is coming from this area --->" That should be enough to get a better diagnoses from the folks here.

It�s your Slave Cylinder,$20-40 part at most, search where it is on your car and when you find it put a little pressure on the plate it butts up against and the noise should stop and if it does throw a new one in easy fix.

....

It was the clutch slave cylinder. But the shift fork itself was also damaged and needed to be replaced as well. Because I didn't know the condition of the the clutch and flywheel because they were aftermarket nor the quality of the install I went ahead and had them both replaced. Turned this into a big job, but as least I know what's in my car. Needless to say, drivability has improved, and the chirping sound is 100% gone.