transmission on 1997 Chevrolet Venture

have to warmup and rev the gas and the trans will catch then ride good all day could this be the presser control selinoid and what is the procedure to fix it.problem ocures when sits for a few hours or overnight

Asked by for the 1997 Chevrolet Venture
Have the transmission serviced... Possible restricted filter or leaking filter o-ring.... Cool fluid is harder for the pump to pull up into the filter, especially if any leaks or a restriction is present ..... (POSSIBLE!)