Today's emission control technology for mixture concentration in real time monitoring and compensation, or air leak is still able to maintain emission test system works. But if the vacuum tubes got sick for a long time, will certainly cause the occupants to driving comfort reduced complaints. Vacuum tube located between the compact complex Powertrain parts, made a very simple Visual inspection is difficult, not to mention the deep hinterland of field trips. Vacuum tubes are close (or resting) top of the exhaust manifold and the cylinder, there are potential dangers. In addition, the vacuum tube from the EGR exhaust gas recirculation device of input signal near by, and along the hood by the battery pack below, both sharp thin edge in these areas, and the possibility of battery acid leakage, so vacuum tube are easily damaged.