Originally posted by gemcleod
I was having trouble with my auto transmission because it wouldn't change into 3rd gear, and was running rough. I discovered that a small metal tube spanning from the engine bloc to the transmission was disconnected. When I re-connected it, the car ran fine. Does anyone know what this tube could be?

its the vac. line going from the motor to your modulator valve on the trans. you had a vac. leak making the motor rum rough and your trans couldn't shift because you modulator valve wasn't working.