thanks for the info matey
just turned the car over and checked the inlet plenum looks like its working fine (Hold up 5 sec). But the vacuum actuator can be move up with my fingers with engine not running but very strong resistance and does not close slowly when i let go it closes instantly. i started the car up and it pulls up slowly . i'm no macanic so bare with me. thanks
Strong resistance; there is quite a strong spring in the actuator, so this may be normal.
But once the motor starts, this can operate immediately (made me jump when it moved so quickly, I was expecting progressive movement)
Sounds like your vacuum is compromised; check the tubing for the whole vacuum system (almost all is on top of the inlet manifold) and look for loose connections (most likely) and split hoses.
You can get the feeling of the actuators by disconnecting the hose leading to each (either end, for ease); when connected to a good hose, it should feel different, and if it doesn't, the problem may lie in that area.
Finally, check the pump (with engine running) to confirm it is pulling a decent vacuum.
Think of the system in normal terms; the pump provides the muscle, a reservoir to provide stamina, a control to determine when the actuator should work (and how hard) and finally the actuator to do the work.
response and poor hold-up for the shut-off leads me to suspect the vacuum "muscle" is insufficient, either by poor pumping, or by leaks wasting that pumped effort, or even the reservoir (behind the inlet manifold) being clogged and removing the stamina.