Hi steve,
yeah if you didn't get much flow when you pressurized it with air then it may be stopped up. If your using flush i wouldn't run it in there more than a day, that stuff is pretty caustic and might damage something if you run it too long.
What i wound up doing when i ran into that is finding a zip tie, or a piece of semistiff wire that's long or something that i could snake through there and break that stuff up. Just try and narrow down the part of the system the clog is in. In my case it was in the bypass part of the intake and poking something through there broke the stuff up and then i flushed it out. Also make sure those hoses are in good contiditon too on the inside, if they are hard or cracked at all i would replace them.