Canon Pixma IP4000 cyan ink will not flow even though I have repeatedly cleaned and deep cleaned and replaced ink tank.

If you have gone through the process of cleaning and deep cleaning, as described by canon, and you still get no ink flow after printing 2-3 pages, the print head needs to be replaced.
Here is WHO to contact and HOW to install the print head:
WHO: Purchasing a Print Head
You may purchase a print head* for this printer by calling 1-800-828-4040 Monday-Sunday 8:00 a.m. - 12:00 midnight. EST, excluding holidays. When calling, speak the term "order parts" when the speech routing system asks the reason for your call. You will immediately be routed to the Parts Desk for assistance. Be sure to have your model number (iP4000R) or part number (QY6-0049-000) ready for the sales person.

HOW: Install the print head and ink tanks correctly iP4000/iP4000R/iP5000

Seat the print head Below is the procedure for seating the print head and ink tanks:

1. Power on the printer.
   
   
2. Open the paper output tray and top cover.
   
   Note: Gently open the paper output tray while holding it.
   
   
3. After confirming that the print head holder has moved to the center, open the inner cover.
   
   
4. Remove the orange tape securing the print head lock lever, and raise the print head lock lever.
   
   Note: If the top cover is left open for more than 10 minutes, the print head holder will move to the right. If this occurs, close the top cover once and then re-open it.
   
   
5. Remove the print head from its package and remove the orange protective cap.
   
   
   
   
   
   <1> Electrical Contacts and Print Head Face's Nozzle Area
   <2> Ink Supply Filters
   
   Note: To avoid any damage, do not touch the print head face's nozzle area, electrical contacts, and ink supply filters. After removing the protective cap, set the print head into the print head holder immediately. Do not re-attach the protective cap after it has been removed.
   
   
6. Set the print head into the print head holder, and lower the print head lock leCanon Pixma IP4000 cyan ink will not flow even - set_print_head_3.gifund is made.
   
   
   
   Next, install the ink tanks.
   
   
7. Remove the cyan ink tank (BCI-6C) from its package. Pull Canon Pixma IP4000 cyan ink will not flow even - set_print_head_4.jpghe direction of the arrow to remove the wrap film completely.
   
   
   
   
   
   <1> Removed correctly
   <2> Removed incorrectly
   
   
8. Hold the ink tank as shown in the image below. Twist the orange protecCanon Pixma IP4000 cyan ink will not flow even - set_print_head_6.jpgction of the arrow, and remove it.
   
   Note: Remove the protective cap while holding it, so that fingers will not be stained by the ink.
   
   
   
9. Insert the ink tank into the slot at the right end, and push down on the PUSH mark on top of the ink tank until a click sound is made. Install the other ink tanks in tCanon Pixma IP4000 cyan ink will not flow even - set_print_head_8.jpg/>
   
   
   
10. Close the inner cover and top cover.
    
    Note: Check that each ink tank is installed in the correct position:
    
    
    
    Properly installed: