The invention relates to a motor vehicle having a power train wherein the engine can drive an automatic transmission by way of an automatic clutch. The disclosed invention provides a system for detecting and removing tube obstructions, as well as an automated process for verifying the flow rate for each tube and identifying tubes with abnormal flow rates to remove a source of human error and conserve labor costs. A second well doping is performed on the first middle portion when the mask is on the second middle portion. The second spread spectrum signals are received at the plurality of antennas. An output time of the second bias is longer than an output time of the first bias.