I have read 10" to 20" at idle from the line to the modulator, and I have read zero or nearly zero and full throttle. What about everywhere else between idle and full throttle. I am getting clunky shifts and feel that I don't have enough vacuum with light to medium throttle accelleration. I have a feeling that my vacuum control valve is not working as it should, and that it should be decreasing vacuum to the modulator in a more gradual way as the throttle position increases.