I have 4900. It was running fine, with a humidifier keeping it between 45-50% humidity. On a print the black channel stopped completely. Left a green blob where black was supposed to be. Did nozzle check, no black ink, tried level 1 clean, did execute powerful, switched from photo to matte and back, ran about 40 test print pages of either just black or print targets, no relief. Maybe one mark, no numbers or letters under print nozzle check (which should be in black). Got piezo flush for the photo black and ran initial fill. Got a pattern with piezo flush, even letters, some minor lines not filled, but felt relieved. Left it overnight to soak.
Tried a print check, still missing some, so ran an auto nozzle check. Three clogged heads noticed (PK, Y & LC with small breaks). Competed the cleaning an ran a nozzle check. Absolutely no piezo flush printed in PK. One day and back to completely gone. Tried to run a paired cleaning, did multiple test print pages, some only of the PK, switched from PK to MK and back, nothing.
First big possible issue. I forgot to pull the vent tab on the piezo flush cartridge that was about 2/3 full. When I removed the cartridge and pulled the tab when I realized this after the initial fill, I heard air being sucked in the vent. I replaced it and have not yet run another initial fill.
Would air in the system be a cause of this, and what do I do to fix this? Do I do a full right side piezoflush to see if it recovers and run again? Not crazy about pumping good ink into the maintenance cartridge.
I bought this in 2012. Not a real heavy user, but print each week. Had a major clog last February that lots of ink and cleanings solved. Good for about 11 months and then this.
I am wondering if it is best to see if this is a goner to get the other 4 cartridges for the right side of the printer and run an initial fill at least once a day for a couple of days to see if this repeats itself. I am not hopeful of investing more in ink and time if this is as bad as I fear. I can buy a Canon 24" printer for the price of the print head and service call and ink and supplies.