That "little rubber hose" is a vacuum line... When the diaphragm in the regulator goes bad it can leak gas and fill up the vacuum line... Doesn't always work that way,,, BUT,,, it is a pretty good indication of a bad FPR... I had actually forgotten about that "trick"... As I said (somewhere not too long ago) I haven't had or worked on ANY GM product in quite a few years... I haven't even had a car or driven since last Feb... Can't afford much,,, but,,, I am looking!!! I'm stuck in a rest home for now and it really sucks not being able to go anywhere!!!
Tom B...