ok i just changed my belt tensinor and adjusted valves on my car this week hehe, im sure that you can do it with out messing anything up.

pull off the driver side tire then there is a little rubber plug on the cover for the timing belt. you lossen the tensionr bolt (behind the plug) then i rocked mine back and forth a few times (not full turns just a little tug and then in the opisite direction) i had my valve cover off and the belt cover off so im not really sure how easy its gunna be to do this with those on but still might want to give it a shot :\

i have one thing to say to the guy that you got the car from. IDIOT, he was right there jessus... lol have fun

pm if you dont understand lol