someone pointed out that the heater tap on the right side of the engine bay is missing the vacuum hose.There is only one hose i can see coming from the firewall and it runs to the left side and attaches to a cylindrical metal thing about 6 inches wide located under the left front guard to the front of the wheel arch.I am referring to left and right from looking at the engine bay from the rear of 6the car
That vacuum line is going to the reservoir. More then likely, the tap is seized with rust. Located on the drivers side, below the booster near the manifolds. You will see the heater hoses going to it
also possible that the control inside car is not turning completely off. Check behind console near driver's left foot where the rod that is operated when you use the heater contol sticks out. See if you can move the nylon part attached to rod further in the off position. On my VP there is a button that gets pushed in by the last bit of movement of the bracket. The nylon clip that secures bracket to control rod can be unclipped and adjusted if necessary. Do both in the fully off position. bit of a nack to unclipping bracket so be careful not to break it. I was able to get a new one from holden about 2 years ago. Or the heater tap is seized with rust.
