【Inspection process】
    First check the oil situation, oil flow, gasoline atomization into the tank, there is no exception. Check the high-voltage circuit, the central high-voltage lines and the sub-line line are fire, and the spark is strong, no string leakage. Check the ignition device in advance, the fixing screw is not loose. Remove the spark plug detection, flash normal. Remove the timing belt cover inspection, the belt without breaking and wear. After the inspection found that the ignition is not correct, after the correction test, still can not start. Check the ignition again, still not the time. Dismantling the crankshaft timing gear, found its fixed bolt loose, shaft hole wear is too large, can not be synchronized with the crankshaft rotation, the replacement, the engine can start.
    【Fault Analysis】
    Due to the timing of the gear fixing bolts loose, resulting in timing gear and crankshaft front end is not tight, over time, the shaft hole wear is too large, it can not be synchronized with the crankshaft; through the timing belt conduction, camshaft can not be the same with the crankshaft Fixed gear ratio. And then the cylinder into the exhaust valve can not according to the work of the cylinder and the requirements of timely and orderly opening and closing, so that the ignition serious disorder, resulting in the engine can not start.