Digital BW, The Print

1160 printer.
MIS vm-s inks with CFS system.

Symptoms:
Poor prints that look like the inking system has to be checked.
Bad nozzle check pattern with missing bars and sometimes an entire 
segment is missing (the bottom row, centre pattern). On one occasion 
I also had a pattern where some bars were out of position.
Run cleaning cycles which have resulted in a Good nozzle check 
pattern, but after doing a print it's clear to see poor print inking 
again (lack of depth/tone/deensity etc). Run another nozzle check 
after the print - Bad nozzle yet again. The Good nozzle check doesn't 
last
I also printed a 4 col purge pattern (MIS) after getting a good 
nozzle check, which printed successfully.
Do another cleaning cycle and get a Good nozzle, do a print, check 
nozzle, bad again - recurring over and over.

Attempted cures:
1.Paper towel with Windex under the print head path.
2.Drops of Windex on the parking pads.
3. Three cleaning cycles in quick succession, without a nozzle check, 
and let stand for a couple of hours.

What else can be done ?

I searched old posts and it seems that replacing the CFS with Epson 
ink carts is also recommended - correct ?
If so, how do I do this - I can see if I were using carts presently, 
but with a CFS ?
thanks,
Frank