A new type of clutch problem

[CTS03]

In the last 2-3 days I realized the following problem of the clutch in my Corolla TS (Sportivo):

When I start the car, I put rear gear and I release gradually the clutch pedal to go slowly out of the parking site. However, the operation of the clutch cannot have a linear effect but it vibrates the engine (I try to keep it on). Like if the clutch could be operated only in two states (fully engaged or disengaged), without any slipping capability.

I noticed also a bird's song type of noise in the engine compartment. I can reproduce it by standing the car with no gear (neutral), each time I press down and then release the clutch pedal. This noise starts immediately with the release of the clutch pedal and then decays after half a minute.

Another strange thing is that these problems occur rather randomly, I would say in half of the occasions.

Have you any idea what is wrong in the clutch system ? I have no evidence for any clutch slippage problem.

[Dead]

Is it just reverese where this happens?

I'm a noob, but I'm thinking it could be the clutch plate not engaging properly?

[Seano]

My guess is its going to be something with the hydraulics, especially if its making noise while pressing in the clutch while in nuetral. I'd start looking at the master cylnder for the clutch system - best bet is to take it to a mechanic

[CTS03]

According to a mechanic, the noise is from the clutch ball-bearing.

The other problem indicates a worn clutch disk (not tested though). It happens randomly for cold engine and it could be noticed both in 1st or rear, but it is mainly noticeable in rear due to a slower move (less gas). But normaly I could not wear this disk!!! It has about 40K km, I drive carefully, it was almost never smelled after replacing an initial easily smelling disk.

I think something may be also wrong with the hydraulics of the clutch system. The clutch-gearbox is anyway the worst part of this car.

Edited March 18, 2008 by CTS03

[MT]

How many km's have you done? The clutch throwout/thrust bearing is the source of the noise when the clutch pedal is depressed.

If the car has high k's, just replace the entire clutch with an Excedy HD unit.

[CTS03]

How many km's have you done? The clutch throwout/thrust bearing is the source of the noise when the clutch pedal is depressed.

If the car has high k's, just replace the entire clutch with an Excedy HD unit.

The clutch has about 40-45K km and the "bird's song" noise happens when I release the pedal.

However, a n additional noise, a kind of metallic "clunk", also appeared now when I press down the pedal (at the bottom of its travel) and the car is cold. I guess this could not be due also to the throwout/thrust bearing?

[qkslvr]

Definitely the throw out bearing. if you hold the clutch pedal down while you're at traffic lights or you slip your clutch alot then it puts undue stress and extra wear on the thrust bearings and pressure plate.

either way, you'll need a new clutch.

[CTS03]

Definitely the throw out bearing. if you hold the clutch pedal down while you're at traffic lights or you slip your clutch alot

I certainly do the opposite! However, this new clutch was installed with a rather abrupt operation (short travel for engagement) after I complained for an easily smelling/slipping (long travel) one. Perhaps its "abrupt" operation may increase the stress on the bearing and pressure plate?

If this indeed happened, then it seems impossible to have a good compomise in the operation of these Toyota clutches.