Had a timing belt go on my 2000 Impreza Outback Sport 2.2l. Got some info off the net and lined the marks up installed the belt, and it won't run without my foot on it; very rough, won't idle on its own. I assumed that my #1 Piston would be top dead center when the camshaft mark is on top but it is not? Why? Not sure what my next steps are, valve damage? Compression test? What could I be missing? Any help would be appreciated.