Clutch Delay valve

[Serge]

It seems that my car has developed a noise that Les Interenate describes as the Clutch Delay Valve.

One described it best as the sound of "a muted goose"

Since this car is essentially a Subaru (even though the tranny is out a lexus? Or is that the diff) anyway I figure maybe some of you have this on the modern cars.

It seems to only happen when the clutch engages too fast or too slow (if I drag it) and only at high RPMS/load.

Something to worry about? I'm at 5000km and it hasn't been doing this previously.

[LaszloT]

Serge, I don't get out much so what vehicle/engine/tranny combo are you referring to?

I need to literally drop my clutch and bog the engine or I end up with tons of clutch smell and some smoke.

[Serge]

I'm referring to the Scion FRS.

[JoeT]

The clutch delay valve is installed in ALL subaru's from 2004 onwards, it's to prevent deadly driveline shock by sacrificing the clutch. It's located on top of the slave cylinder, it looks like a 6 sided long nut with the steel tube on top which goes to the clutch master cylinder and the bottom which goes to the actual clutch slave cylinder. The groan you're hearing may not be the delay valve as it's a simple leaky check valve setup that lets out pressure at a predetermined rate. There shouldn't be a noise from it unless there was air in the system.

The muted goose sound is more the characteristic of a 'Glased' clutch friction disk actually.

[Serge]

found another dude with the same problem

you can hear it here, i'm hoping it's just something resonating but dunno.

http://www.youtube.com/watch?feature=player_embedded&v=-zsPn6YMf5g

[STeveD]

So it's happening about 1 second after the clutch is re-engaging during acceleration? Sounds like a vibrating metal sound when you're getting back on the throttle?

[Serge]

sort, i guess

but only when i drag the clutch or throttle

if i clutch out with my foot off the gas, nothing happens

if i clutch "properly" nothing happens

if i get a bit lazy and keep tiny amount of pressure on the throttle the noise appears during the point of engagement, not after, but right during.

if i'm driving on the highway and i can "maintain" the noise by getting the clutch to slip just the right amount with clutch/throttle balancing.

[JoeT]

Really sounds like a glazed clutch.