Car clunking

Clunking when the car is standing still and you're turning the steering wheel is usually caused by binding upper strut mounts. To verify that, reach over the top of the tire and lightly touch or wrap your fingertips around the coil spring. Have a helper slowly turn the steering wheel between full-left and full-right. You should feel the spring rotate smoothly with the wheel and tire. If the upper mount is binding, you'll feel the spring wind up and build tension, then suddenly snap free and turn.

It's very rare for an upper mount to bind while the car is moving unless one is really bad.