Hear a "knocking" sound coming from my front left wheel when I press on the brakes

Hi 1clayton3,

If the knocking noise is repetitive while the wheels are turning, then most probably the rotor has a dent or bump along the edges.

If the knock is a one time noise each time the brake pedal is depressed, you have to look out for worn castor bar bushes, lower arm bushes and ball joints, steering linkages, loose or worn slider bolts and improperly torqued wheel lugs.