Twisted

Another member's post reminded me of something I've been meaning to ask for years: My idle in general is great; it always idles at 750, and never hangs or fluctuates. However, it's always been slightly lumpy as though from an aftermarket cam...but milder. You can physically feel it--particularly when the car is cold. The stock (as far as I know) motor runsunusually strong, and has no other issues. Could a bad cannister purge solenoid (code 85) in any way cause me to have a slightly lumpy idle?

By the way, when I say slightly lumpy, I mean that when the car is fully warmed up, a passenger probably wouldn't even notice it.