The mileage is about 5000km, and the 2014 modern maps of Beijing are equipped with 1.8L engines and manual transmission. When the customer arrives at the store, it is reflected that the shift lever can not be successfully pushed into the corresponding gear when the first gear is hung in the morning, but when the second shift lever is pushed into the same gear, the shift lever can be pushed into the gear smoothly. When the maintenance personnel pick up the car, first verify the customer's complaint, when the clutch pedal is pushed into the reverse gear after stepping on the clutch pedal, the shift lever cannot clear Off, and the profit is pushed into the reverse gear, but when the shift lever is put to the gap, the shift lever can be pushed into the reverse gear, but the shift lever can push the block into the reverse gear. In accordance with the above method, the maintenance personnel tested other gears, and found that the 1 block, the 2 gear and the 3 gear also had the same problem. However, in the fault inspection, the maintenance personnel also found that if the clutch pedal continued to keep about 5S more than the time to keep gear, basically there is no gear difficulties. According to our detection of the vehicle's malfunction, we can preliminarily determine the possible reasons for the failure: (1) the clutch is not completely separated. (2) the position of the shift lever is not adjusted. (3) the type of manual transmission oil does not match. (4) internal fault of transmission. Because this is a brand-new car, the manual transmission oil is the original factory transmission oil filled in the factory, so in the transmission oil, we just checked whether the transmission oil is sufficient and the result of the inspection is normal. Then we checked the location of the shift lever according to the requirements of the maintenance manual. This is also no problem. Considering that the transmission itself is unlikely to cause problems, and even if there are problems, it can not be reverse gear, 1 gears, 2 gears and 3 gears at the same time. So in the end, we have delineated the cause of the failure in the incomplete separation of the clutch. There are two reasons for the incomplete separation of clutch, one is clutch operation part, such as clutch master cylinder, clutch sub pump, clutch separation fork. On the other hand, the clutch body part, such as clutch pressure plate or clutch disc. So in the following fault inspection, we checked the clutch general pump, the clutch sub pump, and the operation of the clutch split pump, and also checked the movement of the clutch split fork from the outside. All of these checks did not find any problems and finally repaired. The personnel can only remove the transmission and check the clutch body. After disassembling the transmission, we found that the slot of the input shaft of the transmission was covered with rust, and the inner spline of the clutch that was meshed with it was also rusty. We loaded the clutch disc on the transmission input shaft and found that the movement of the clutch plate was not TIC smooth when the clutch was slid. Use wire brush to remove rust on the input shaft of the transmission, then use rust remover and file to clean the rust on the splines of the clutch disc. After completing the cleaning work, reassemble the transmission, and troubleshooting at the last test run. Fault summary: the cause of the failure of the car is caused by the rust on the input shaft of the transmission and the spline inside the clutch, which causes the clutch in the process of separation, and the clutch disc is stuck in the sliding MOW sliding on the gear, which causes the clutch short time separation. In the actual fault inspection, when the maintenance personnel step on the clutch pedal, the shift lever can be normally hung up when the clutch pedal is extended. This phenomenon also indirectly proves the problem that the 3 is from the initial time.