I spoke with my Mopar Transmission builder . He had knowledge of this line . He said it ran up to something that had to do with retarding timing momentarily coordinating the shift with governor pressure for a smoother shift . He said it only came on a couple models like a Matador . He was a lot more detailed on his explanation , but I could only get a grasp of the basics , as it was a quick phone conversation . He said to put plug/cap at the transmission and Forget about it !