I watched the turbo on youtube, I only know the basic on turbo mechanism. Exhaust gas to turn on the high speed shaft, that shaft copress the intake air (passenger side) and send the intake air to the cooling stuff (enters at the passenger side and exit at the drive side), the air then enters engine at the driver side. the item 1 - item 4 are connected to the cylinder, that is the control unit for the wastegate (behind the heat shield), I understand that the wastegate is controled, to open when the turbo compression is too high, to relieve some pressure by opening the wastegate. My blind point is how this hose, connected to the cylinder (wastegate controller), control the wastegate, I guess that is a pressure controlled mechanism, and when the pressure is too high, it opens the wastegate, maybe someother hose to cooling as well.
Please enlighten me.