When the car travels at speeds ranging from 40 km/h to 70 km/h, the engine shrugs. If the speed is lower than (above) 40km/h or 70km/h, the phenomenon of "shrugging" will disappear, especially after shifting from 3rd to 4th gear, the speed will be accelerated sharply at this time, and the power of the engine will be dull and the power shortage is obvious. If we use four-wheel drive (four-wheel drive), sometimes there will be flameout. If we use two-wheel drive, the problem will be alleviated.

　　毛病检查与排除：根据车主提供的毛病现象进行路试，感觉问题应该在焚烧体系上。用表丈量高压线阻值，2缸高压线阻值偏大，替换原厂高压线，路试后毛病现象消失。然而几天后车主抱怨，替换高压线后仅仅正常行进了5天，现在“耸车”现象又呈现了。车主怀疑高压线的质量有问题，要求重新替换一套新的高压线，为了断定高压线质量是否有问题，选用换件法和相同的车交换高压线，比较后“耸车”现象仍是没有消失，这说明高压线正常。检查火花塞时发现火花塞为非原厂火花塞，全部替换原厂火花塞后试车，毛病现象消失。原以为这次能完全排除毛病，可是3天后车主又把车开回来，抱怨“耸车”现象又呈现了。

　　Inspection and elimination of faults: According to the phenomenon of faults provided by the owner of the road test, the sensory problem should be in the incineration system. Measuring the resistance of high-voltage line with meter, the resistance of high-voltage line of 2 cylinders is too large, replacing the original high-voltage line, the fault phenomenon disappears after road test. However, a few days later, the owner complained that he had only gone five days normally after replacing the high-voltage line, and now the phenomenon of "shrugging" has appeared again. The owner suspects that the quality of the high-voltage line is not good, and requests to replace a new set of high-voltage line. In order to determine whether the quality of the high-voltage line is bad, the replacement method and the same car exchange high-voltage line are selected. After comparison, the phenomenon of "shrugging" still does not disappear, which shows that the high-voltage line is normal. When checking the spark plug, it is found that the spark plug is not the original spark plug. After replacing the original spark plug, the test run will be completed, and the fault will disappear. I thought I could get rid of the problem completely this time, but three days later, the car owner drove back and complained about the phenomenon of "shrugging" again.

　　为什么替换完高压线、火花塞后，毛病现象就会当即消失，而过几天又呈现呢?由于缺乏相应的检测设备，对这种奇怪的毛病现象也无法解释。只好向修理站的朋友咨询，他说这种毛病现象应该替换原厂火花塞，我告诉他火花塞已替换成原厂配件，但朋友怀疑火花塞的质量有问题，于是朋友下班后把从修理站带来的火花塞安装好后试车，毛病消失。根据以前的状况主张车主再行进几天观察一下，半个月后车主打来电话反应“耸车”现象再也没有呈现。

　　Why does the defect disappear immediately after replacing the high-voltage wire and spark plug and appear again in a few days? Because of the lack of corresponding detection equipment, this strange defect phenomenon can not be explained. I told him that the spark plug had been replaced by the original spare parts, but my friend suspected that the quality of the spark plug was not good, so the friend installed the spark plug from the repair station after work and tested it, and the problem disappeared. According to the previous situation, it is advocated that the car owner should travel for a few days to observe, and half a month later, the car owner calls to respond to the phenomenon of "shrugging" no longer appears.

　　毛病总结：在替换火花塞时应特别注意火花塞的热值是否契合原厂规范。一些修理界的同行在工作中往往替换火花塞时随意性很大，有时认为高的火花塞必定比低的火花塞好，就像铂金火花塞比一般型火花塞强相同，铂金火花塞焚烧时减轻了在燃烧室内的电火花、烧蚀和腐蚀现象，并且发生更强的火花，寿数也比一般火花塞大大提高，可是并非适宜每台发动机。一些个别修理企业或修配厂购买的火花塞质量很差，单凭配件的外观很难区分其质量的好坏，因而我们在工作中就会无法做出正确的判别。

　　Summary of faults: When replacing spark plugs, special attention should be paid to whether the calorific value of spark plugs conforms to the original factory specifications. Some repair professionals tend to replace spark plugs at random in their work. Sometimes they think that high-priced spark plugs are better than low-priced spark plugs. Just as platinum spark plugs are stronger than ordinary spark plugs, platinum spark plugs reduce the phenomenon of spark, ablation and corrosion in the combustion chamber when they are burned, and produce stronger sparks, and have a longer life than ordinary spark plugs. Great improvement, but not for every engine. The quality of spark plugs purchased by some repair enterprises or repair factories is very poor. It is difficult to distinguish the quality of spark plugs by their appearance alone, so we can not make a correct judgment in our work