Not sure if this is the answer, but I had a similar problem but with both black and colour. The only cure seemed to be to replace the whole printed. A fidderly job, but not impossible. The part no. is F083030.
The Epson print heads do not seem to like being cleaned much. Be careful when attempting repairs on Epson printers, the electonics can be damaged by moving the carriage by hand. It seems to create a voltage (the motor seems to act like a dynamo when turned by hand) which can cause problems on the circuit boards.
A.H., November 2008
