Weird front-end noise...
 

Every now and then, I'll get a thep-thep-thep-thep noise coming somewhere from the front of the car. It's speed increases with vehicle speed. It can be heard outside the car. I can feel a light vibration come through my left foot when I place it where the dead pedal would be.

Sometimes the car makes this noise, sometimes it doesn't.

Turning doesn't change the noise.

It made the noise on the way to dinner, but not the way back.

It seems to either make the noise for an entire leg of a trip, or not at all. I don't think it will start mid-trip.

Any ideas?

I'd check the sway bar mounting points, also check the shocks (inserts) and hte steering rack for proper operation. While you are there, check and retorque the steering components as needed...

Since it is speed-dependent, I would also check the left front tire for signs of delamination. Look for a slight bulge somewhere on the tread ar a spot of unusual wear.
Good luck.
Les

Anything loose in your trunk that could move around sometimes?