The car suddenly turned off in the downhill, the driver will be linked to the transmission on the 4 block, would like to use the transmission system torque to start the engine, but tried a few times did not succeed. Car slide to the bottom of the slope, and then start the machine crank crank, found very laborious.
    Diagnosis and exclusion
    From the fault phenomenon, it seems like a timing belt break. In order to confirm, with the sleeve to turn the crankshaft, found that the camshaft does not turn, remove the timing belt front cover, found that the timing belt really broken. Take the new timing belt, press the timing mark to change the timing belt, start the engine, feel the starting machine with the crankshaft. Thought that the battery power loss, so with the new battery in parallel to start, but still feel the starting machine with crankshaft.
    In the event of a failure, the starter is working properly. So with the sleeve and then turn the crankshaft, when turned to a certain angle, the crankshaft can not turn, suspected that the piston will be the top of the valve. Because from the structure of the Jetta engine, the valve and the piston prone to interference, that is, when the engine is chaotic, the piston and the valve collide. Remove the cylinder head check and found that the third and fourth cylinder of the intake valve bent, and in the cylinder of the piston left the traces of the impact. Remove all valves and check the replacement valve. Do not install the cylinder head in the case, shake the crankshaft, check the piston rod is deformed, bending, after checking the normal. The engine assembly is good, start the engine, work properly.
    Analysis of the cause of the failure is down when the belt is broken, forced to stop when the valve will start the top of the valve, resulting in a new timing when the belt can not start the engine.