Power Issue with my 2014 RZR 4 800

Needing some suggestions on what my problem may be. I just got my ride back from being stolen, so I have had to replace many things on this bike. The issue that I am currently having is no top end power. When I first started working on it, it would cut in and out. So I thought it may be injector going out. Cranks fine, but when I give it gas its acts like it may be choking down. I checked my spark plugs to see if I was getting fuel and one side is dry. Almost like it not getting any fuel. Does anyone have any suggestions of what may be going on?