My HP psc 1210 multifunction printer (2.5 years old) has developed the habit of producing smudged horizontal lines across the page when printing in black. This happens quite often, in about two places in a document. I have cleaned the print cartridges, what else could I do - or is the printer on its way out? Thanks in advance.
If the smudging happens in the same place every time then it suggests that the problem is mechanical - check that all the paper rollers are free of dirt, old ink and dust and that they move freely. To help movement,use a small paintbrush to apply a (very) small of WD40 around the spindle.
Some printers have a waste ink tank- where overflow and that used in clean processes drains to. This in time will top up and need cleaning out. Does this apply to you particular model? Spuds suggestion may have an answer.