Auto transmission is acting up in my V6 2004 Sonata, 111k miles. Car has trouble shifting to and from 2nd gear, but only when loitering in that range (i.e. 20-30 mph). It will wait until approx. 3600rpm and shift uneasily to and from 2nd. When rapidly accelerating, it's basically a non issue, and the gear can be manually set up or down without problems. Tansmission fluid was dirty (no metal) so I changed that out and it ran a bit smoother. Just replaced input/output sensors, check engine light went away but issue persists. Not sure where to go from here.