Sometimes, I can get the wipers to work just fine, then other times the right one won't go up. It will go just a little, like it is making an effort, but just can't do it. Could it have anything to do with the wiper arms being too long? I have the size that the auto store told me to buy but they are too long, the left one gets caught under the right one, and the right one hangs off a little. With winter coming I would really like to resolve this issue, if possible.
Put the correct length wiper blades on the arms and with both wiper arms down at the base of the windshield pop up the caps where the wiper arm nuts are. See if the 13mm nuts are loose. Let me know what you find.