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.

　　毛病檢查與排除：根據車主提供的毛病現象進行路試，感覺問題應該在焚燒體系上。用表丈量高壓線阻值，2缸高壓線阻值偏大，替換原廠高壓線，路試后毛病現象消失。然而幾天后車主抱怨，替換高壓線后僅僅正常行進了5天，現在“聳車”現象又呈現了。車主懷疑高壓線的質量有問題，要求重新替換一套新的高壓線，為了斷定高壓線質量是否有問題，選用換件法和相同的車交換高壓線，比較后“聳車”現象仍是沒有消失，這說明高壓線正常。檢查火花塞時發現火花塞為非原廠火花塞，全部替換原廠火花塞后試車，毛病現象消失。原以為這次能完全排除毛病，可是3天后車主又把車開回來，抱怨“聳車”現象又呈現了。

　　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.

　　為什么替換完高壓線、火花塞后，毛病現象就會當即消失，而過幾天又呈現呢?由于缺乏相應的檢測設備，對這種奇怪的毛病現象也無法解釋。只好向修理站的朋友咨詢，他說這種毛病現象應該替換原廠火花塞，我告訴他火花塞已替換成原廠配件，但朋友懷疑火花塞的質量有問題，于是朋友下班后把從修理站帶來的火花塞安裝好后試車，毛病消失。根據以前的狀況主張車主再行進幾天觀察一下，半個月后車主打來電話反應“聳車”現象再也沒有呈現。

　　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.

　　毛病總結：在替換火花塞時應特別注意火花塞的熱值是否契合原廠規范。一些修理界的同行在工作中往往替換火花塞時隨意性很大，有時認為價格高的火花塞必定比價格低的火花塞好，就像鉑金火花塞比一般型火花塞強相同，鉑金火花塞焚燒時減輕了在燃燒室內的電火花、燒蝕和腐蝕現象，并且發生更強的火花，壽數也比一般火花塞大大提高，可是并非適宜每臺發動機。一些個別修理企業或修配廠購買的火花塞質量很差，單憑配件的外觀很難區分其質量的好壞，因而我們在工作中就會無法做出正確的判別。

　　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