Greyscale printing with cyan colors for some reason

[Niels_Peter]

So yesterday is was trying to print a set of photos in greyscale, and they came out great. Images was sharp and the grey was clean on nice looking (a little bit of a brown tint, which works great).

Today i went to print exactely the same, but now the colors or nowhere near the same. I'm using the same paper, with the same settings (greyscale), and the printer is not warning against any cartridges being close to empty. But for som reason, the greyscale is muuuuch worse now. A lot of the time, they shadows are being printed using cyan, which is not greyscale at all. And the pictures just looks more "plain" og lack the same quality (also seems like that nice brownish "vintage" tint has dissapeared. I tried printing once where is forced the printer to use "only black" instead of "high quality grey scale", and sure enought the cyan dissappeared, but those images are on the other hand much more grainy and just poor quality, so that doesn't really help.

What can i do? what am i doing wrong? i have literally changed nothing in the settings, yet the images are nowhere near the same quality.

"before and after"

[Valsimot · Accepted solution]

Can you print something in black to see will it be in true black.

When printing in grayscale printer uses black and colour inks to get better greys, if you have some issue with the black printhead then cyan overcomes black because cyan is mixed with black to get grey.

[Niels_Peter]

Thank you so much for the reply. I tried replacing the photo black inc cartridge, and it must have been lower than i thought, because the colors are back to normal now, and the cyan is no longer overpowering the black