A Passat B5 accident car, had repair the engine in other repair shops, and then appeared in the engine in the hot car flame failure.
    First connect the fault diagnosis VAG1552, open the ignition switch into the engine electronic control system, query the fault code, found a fault code "16496", which means the engine intake air temperature sensor G42 there is a problem. Then choose to read the data block function, into the 003 group to observe the fourth display area, found that the value of -46 ℃, this value is obviously wrong. And then use a multimeter to measure the sensor resistance is also normal, the sensor and the computer wiring harness does not exist in the case of open circuit and short circuit, so the engine computer removed, for a new engine computer, but the failure did not disappear.
    Is it due to the incorrect installation of the engine computer or sensor? And the most likely factor is the plug connection error. After reviewing the maintenance manual, it was found that the intake air temperature sensor harness color is not correct, its color exactly coincides with the harness color of the intake manifold switching valve. The original repair shop outside the repair shop in the installation, the intake air temperature sensor and intake manifold switching valve plug inserted, resulting in a failure. Then, after the two plugs are correctly installed, enter the 003 display group of the VAG1552 reading data block unit again. At this time, the intake air temperature indication of the fourth display area is normal and the fault is eliminated.
    What is the main reason for the failure of the car's hot car after the car? According to the motor engine electronic control system works, if the engine intake air temperature sensor line problems, the computer will use a 195 ℃ alternative signal to maintain the engine work. But if the ambient temperature is high, the engine long-term use of the intake air temperature standby work, hot car after the mixture will be thick, resulting in engine flameout.
    When we are engaged in maintenance work, it may not be in accordance with the experience of the maintenance manual in accordance with the requirements of the assembly manual, resulting in man-made failure, so that maintenance and testing around the bend, so when considering the problem to be comprehensive, careful inspection should be installed in strict accordance with the maintenance manual Requires operation.