Please help! Idling issues.

[FHP0827]

I don't think it's any type of "fouling" issue.......unless it's fouled spark plugs possibly. These engines are always filthy inside since they re circulate crankcase vapor back into the intake, but apparently it doesn't bother them at all. Really sounds like a vacuum leak to me is the most likely cause. Incidentally, what kind of plugs are you running in it? I have found that they really don't seem to like Bosch Platinums for what it's worth.