* Worn timing belt: If the timing belt is worn, it may not be able to grip the sprocket properly, which can cause it to slip off.
* Loose timing belt tensioner: The timing belt tensioner helps to keep the timing belt tight against the sprocket. If the tensioner is loose, it can allow the timing belt to slip off.
* Damaged sprocket: If the sprocket is damaged, it may not be able to hold the timing belt in place, which can cause it to slip off.
In the case of a 1999 Ford Contour, it is most likely that the timing belt is worn or the tensioner is loose. To fix this problem, you will need to replace the timing belt and tensioner.
Here are the steps on how to replace the timing belt and tensioner on a 1999 Ford Contour:
1. Park the car in a safe location and turn off the engine.
2. Disconnect the negative battery terminal.
3. Remove the serpentine belt.
4. Remove the timing belt cover.
5. Locate the timing belt tensioner and loosen the locknut.
6. Turn the tensioner clockwise to release the tension on the timing belt.
7. Remove the timing belt from the sprockets.
8. Install the new timing belt on the sprockets, starting with the crankshaft sprocket.
9. Tighten the tensioner locknut.
10. Reinstall the timing belt cover.
11. Reinstall the serpentine belt.
12. Reconnect the negative battery terminal.
13. Start the engine and check for leaks.
If you are not comfortable performing this repair yourself, you should take your car to a qualified mechanic.
