I own a 1997 golf 3 TDI, motor code AFN.
At the back of the engine, there is a vacuum actuator which looks like a N75 but isn't. It isn't connected to anything on the actuator side, but is connected to the vacuum line and the ECU.
It doesn't seem to have done much to the running, as I cannot detect a difference in power or torque.
Both turbo charge valve actuator (N75) and egr valve actuator are present and accounted for, and I can't see an anti shudder valve anywhere on the intake.
What is it for?
EDIT: Here are some photos;
EDIT 2: When I said "It isn't connected to anything on the actuator side", I mean literally that: there is a vacuum line coming out, but it isn't connected to anything. And I cannot see an obvious connection for it.