Originally Posted by cobalt327
Yes, I believe it's a prob w/the booster. The valve I mentioned has a seat that has to hold vacuum, even a broken/weak internal valve spring has the potential to be the problem, but the booster would need to come apart to confirm this- something that's outside the ability of most guys, besides the poit that you shouldn't need to fix a problem not of your making.
Given the info you've provided and the checks you've made, if it's not the booster, I'm at a loss.
It shouldn't cause the problem, but have you checked the vacuum check valve between the engine and the booster?
Yeah, I checked the valve. All is good.
If no useful help from CPP, I guess I will have to take a gamble and try a different booster from another source. If all else fails, hydroboost it.