Does humidity affect a sensor or other part/regulator on the OM617? I have been running the last few (dry) weeks without even a slight shake from the engine. Today, after a few days rest for the ol' flapjacks, I've got a reasonably shaky idle. It is 71% humidity, and the barometric pressure is 30.03 inches. Is there something to check or clean that might create a shake when the humidity or pressure is high? I can't say it shakes more in the rain, but the barometric pressure is also low when it's raining.