Car wont start after put timing belt on

L have a 98 Ford Contour 2.0 dohc. We replaced the timing belt put it in time and everytime we crank over the engine the exhaust manifold cam pulley will spend and will not turn the cam we've reset the time at least 10 x. Still have same problem with the pulley even if we torked it over 100 lbs. And it still slips on the cam we can take a one inch wrench and turn the cam back and forth and the pulley and belt does not turn just the cam. Why is the exhaust manifold pulley made different what is the sensor in between the cams that is connected to the exhaust cam what is it purpose? Could it be why the pulley will not tighten on the cam? Everytime we've timed it the engine turns over once and fires and the exhaust cam is out of time? We don't think that it is cam possion sensor because the problem is in front of the motor with cam pulley. Thank you hope you can help us