My HP 1220 printer outputs wrong color...What to do???

[jinjen]

Masters,

My HP 1220 printer seems a bit washed out, and when I do a teat page,
it looks as if the YELLOW color does not print out, thus making green look
like light blue, and the red, somewhat cardinal.

I have tried 2 new tri-color original HP cartridges(somewhat old...exp. date
nov. 2001), but with same results. So I am assuming it is not the cartridge
that is at fault.

Pls let me know what I can do.

Thanks in advance.