Have you cleaned the area under the printheads path? The "blue switch" vents are there. You get a lot of ink accumulation in that area. Use an old toothbrush.
For instance, if you print a lot of 17" rolls on your 24" printer, there will be a of ink build up 17 inches to your left of orange arrow marks, where ink overspray is sucked around the 17" paper.
Also, open up the handle and clean the rollers.
Edit: uhoh! Did you just move the printer? The Canons can spill a lot of ink in that situation, I hope that didn't happen to you. I'll let other people respond to that problem.