Hello, I have a small racecar wrap company in Oklahoma. I have been getting lines in my black and it has been banding a little more and more. Last week, I did a nozzle test and a lot of my Black jets were missing. I did a couple of head soaks that were an hour long each, and nothing got any better. I did a head soak over night and still nothing. I then took out my print head and mixed some windex with alcohol and did a manual clean on the head. I put it all back together and my blacks were perfect. The blues were not showing up. I did a bunch of cleaning and nozzle test and they started getting better. I notice some of my yellow was missing, so I kept doing cleanings and it was pretty good and getting better. I did another head soak over night and went back the next day and my yellow was printing like a green color. i kept doing cleanings and started printing just 100% yellow and was getting some green lines and it got a little better. My lines for yellow going to the head were cleared up. I left and came back to my shop today and the left line of yellow going to the head was green and right line of yellow was yellow. So, I guess overnight it is sucking blue into the yellow? Is this possible and if so, what do i need to check? All of my test prints are good and I printed blocks that were 100 of each CMYK and they looked good, except the lines in the yellow of course. They do not get any better. Please help! Thank you ahead of time. I appreciate your knowledge in advance!