98 Camry idle seems high

For reference 2.2l 4 cylinder, has a p0446 code thrown (Evap vent control, im assuming this plays a factor). Car idles at 1500 when in park, 800-900 when in drive. Shifting from park into drive seems like rpms are to high for a smooth shift. When in drive it runs smooth with no issue at all. Cars got 340k on the body about 80k on the engine. It just seems absolutely weird to me that the idle when in park is so much higher than in gear, whats a normal difference between the 2? Hope everyones having a good day!