Clutch Vibration When Depressed

Without opening up the clutch/transmission assembly it's hard to determine the exact cause of this problem. However, based on the experience of many mechanics.autotech will offer the following likely possibilities.

The possible reason why there is clutch vibration when depressed

(1) Loose clutch disc.
(2) Loose pressure plate.
(3) Loose flywheel.

As mentioned, it's difficult if not impossible to determine the exact cause of this problem without opening up the clutch and transmission assembly. However, the diagnosis provided is a very good guess. Why? Well, the reason goes something like this. The flywheel is a round metal plate connected to the engine crankshaft. Therefore, as the engine runs, the flywheel turns.

When the vehicle is in gear and you're driving along, the pressure plate (another round metal plate) is pressing the clutch disc against the flywheel and thus allowing the transfer of engine power to the transmission. So essentially, all three parts are "connected". Now, as the clutch is released (by depressing the clutch pedal), any looseness in any one of these parts will cause that part to wobble and this wobbling will consequently be felt in the clutch pedal.

What to do?

In this situation, let's hope that your car is under warranty, extended warranty, or a service contract. Why? Because a transmission teardown probably cannot be avoided and such work is always expensive. 

However, if the vehicle isn't under any kind of warranty/service contract, try to find a reputable car repair shop since they are extremely reputable and are known for their quality level of work. By the way, if you decide to ignore the problem, it will only get worse and result in an even more expensive repair bill.