HP iiip Streak Problem - Help

[Harvey]

My 11 year old HP iiip was streaking the paper with a 1/4 wide grey/black
streak down the middle. I changed the cartridge (which showed the black
toner on the drum in the middle) and the streak was gone for about ten
pages. It now has showed up on the print-outs with the new cartridge on the
edge of the paper. What can I do to eliminate these streaks?

 

[Harvey]

My 11 year old HP iiip was streaking the paper with a 1/4 wide grey/black
streak down the middle. I changed the cartridge (which showed the black
toner on the drum in the middle) and the streak was gone for about ten
pages. It now has showed up on the print-outs with the new cartridge on the
edge of the paper. What can I do to eliminate these streaks?

I have run the cleaning protocol using the HP iiip generated cleaning paper
with no effect other than I now have 1/2 inch streaks on each end and in the
center.

 

[Harvey]

I have run the cleaning protocol using the HP iiip generated cleaning paper
with no effect other than I now have 1/2 inch streaks on each end and in the
center.

Now I am just getting splotchy grey sheets, even when printing blank sheets.