Suddenly having the same blank page printing problem on my Pixma TR8520, I went through PEdit's steps (save for 5-7), and the print nozzle check pattern test page printed out absolutely fine. But I'm still printing out blank pages from applications. 

I noted, though, that when I went to print out a PDF document from Adobe that was all black text except for a color image of my blue ink signature that I had inserted, only the signature itself printed out. Then it occurred to me to try changing the color of the text in an MS Word document from black to blue to see what would happen. The doc printed out fine with blue text. Going back to black, not at all.

This is not a problem with the black ink cartridges or nozzles. As you can see from the print nozzle check pattern test page below, black printed out just fine. It's only when printing from applications that black doesn't print out. 

I'm totally stumped. This printer is just under 2 years old. I bought it at Best Buy for $80, and the same model is now $180; similar models have had the same jump in price. So it's not as easy to give up on a "cheap" inkjet as it used to be, 'cause they ain't cheap anymore.