you should have 2 different marks on your crank pully, one with 3 slashes and one a little further back with just one slash. the 1 slash mark is TDC, although it may look correct with the ole extension in the cylinder way, its hard to tell if that cylinder is actually building compression. you need to see the marks, and there shouldbe a little plastic tab on your timing belt cover which will help you line them up, also pull your distributor cap off and see if when you reach TDC that the rotor is pointing at the number one terminal in the cap.