Grays Print with Magenta Shade

All my Grays print with a Pink or Magenta Tint. Just replaced print heads and maintenance cartridge. I have attached an image. Any help appreciated.

#1 What printer are you using?

CMYK is purely a printing scheme, which is why we are using yellow and not green.

Light is additive, if you have 100% red, green, and blue you get white, this is what most people are familiar with. In this way the three color pixels in your screen can generate pretty much any color. There are some that have a yellow pixel mixed in to give a bit better yellow definition and brightness control of the color but those are only for very specialized screens.