I have a Canon Pixma iP4500 printer which has gone on the blink.
When I print a 'Nozzle Check' the lines for the individual colours print OK but where the colours should be merged nothing prints. Printing in monochrome works although a bit pale. Printing in colour the first picture is almost OK then subsequent prints have alternate lines blank and the printed lines poor quality. Following pages get progressively worse until the printer is idle for a spell after which the first page is better and then the problem starts again.
The cartridges have plenty ink but it looks to me as if the control of the cartridges is the problem. I have tried the cleaning and deep cleaning processes but that makes no difference.