Randy, You may have already checked this but I didn't see it mentioned in the other posts. There is a small vacuum line that runs from the intake manifold to the flame trap. I have had that hose get plugged solid with gunk on two of my Volvo's. There is also a nipple where the hose attaches to the manifold that has a very small orifice. This is also prone to clogging. I remove the nipple, put it in a vise and run a small drill bit through it to clean it out.