Several things can cause these problems with the Hayward pool cleaner. First, check for improper water flow (which can be adjusted with the flow gauge that comes with your cleaner). Partial blockage of the navigator throat can also cause both of these problems and should be cleared if found. Worn shoes or worn wings can also cause both problems. In addition, there are two other things that could be causing it not to climb (but won't really affect how fast it moves). Check to make sure that the hose isn't too short and that there is not improper ension in the rear flap. Hope this helps. let me know if you have any more questions.