Black line down left side of sheet, if i'm copying a page that is and i can't get rid of it no matter what i try i've changed the drum and the toner and still get a line down the whole sheet

can be the wiper blade, worn out drum, is there a black faint line down the side of the page as well?

You need to locate the source of strikes.
1) remove toner crg., if it has black lines or dirts on drum replace drum.
2) check/clean copy glass
3) use flash light to check fixing section ( Left sideway of copier small doors ) if damadged replace fixing assy.

A) Black Streaks, Shadows, And Ghosting
Adjust the printer's lightness/darkness setting to 2-3 different variables and see if problem disappears. Look at the fusing assembly - is the roller torn or does it have any black buildup? Use caution!!! It gets HOT!

Try another toner also.

I would have to say that you are having a problem with your drum unit and or the developing unit. Most likely the problem is in the drum unit. You have a line going down the page. I would replace the drum unit and try to clean below the drum unit... Good Luck..

don't know the model of machine, but usually caused by the drum unit or toner cartridge. many machines have both drum and toner in 1 unit. try replacing.

Try sliding the blue tab on the drum unit side-to-side. If that does not cure it, you need a new DRUM UNIT

take out toner and shake it to clean the toner cartridge
or you need a new drum

This can be caused by a damaged fuser or drum try to change the cartridge and if that does not resolved the issue then its the fuser

Try running a cleaning sheet through the printer. Remove the drum and check you waste toner (if that is built-in to your drum then skip this). If that gets full, then some of the bad toner can spill out creating lines/smuges. I would also use compressed air to blow out the inside of the printer where the toner/drum goes. That will help remove anything that is left behind after a replacement.

Also, check the settings in the print server for anything that will clean the printer/correct horizontal lines.

Need more info.... Is it pitch line accross the page the whole page or banding on the front or back side of the copies or is it black streaks down the page?