I had my clutch replaced a 1000 miles ago. Now when the clutch is out there is a squeaking noise. If you put any pressure on the clutch it stops. Also when you idle it is a noticeable squeak, squeak, squeak, but if you rev it above 1100 rpm it goes away. I don't know if this is a coincidence but I just replaced the upstream o2 sensor. Before I replaced this the squeak got louder as you revved it higher.