Tonight, I started the car, let it idle down then placed my mechanic's stethoscope directly on the vacuum pump. It sounded normal to me, a "whirring sound" if you will. I did not hear a distinct or stacatto "tick tick tick tick tick" sound.

I then listened carefully to the front of the engine without using my mechanic's stethescope. From up top, I hear a faint tick tick tick tick tick sound coming from somewhere front center of the motor to slightly left of center.

When I listen to the sound from underneath the car, it seems more pronounced than when I am listening standing over the top of the engine. This is puzzling......