we have a well. water is soft. we think the stain is due to copper from pipes.
I don t have a solution here but i have a mk5 astra and i could feel the abs in the peddle when i was just normal braking and now i have a knocking noise when braking and whilst coasting in gear without braking. I am getting it looked at i a day or two so will post the result and probable solition.
Some cars have like these guide pin in the brake hub when the brake pads get to low they hit the disc and sound terrible. I would check your brake pads out.
Sounds like something is wrong with your brakes and/or rotors. You need to get that fixed ASPA, it's dangerous; especially if an emergency braking situation comes up.
I agree with all who said CLR. If still this doesn't work, let bleach soak on the stain for a day.
Blue green stains do come from copper piping if your water is too acidic. A mixture of half water and half ammonia; rinse well and flush pipes with water after using should clear up the stain. I would also have the pH of the water in your well adjusted so it will not continue this because it is technically eating away at your copper piping.
