I Have A 1994 Mercury 2-stroke That Has A Rough Idle That Only Gets Better When You Bump The Choke It Doesnt Matter If It Is Warm Or Cold.also Once You Reach Max Rpms (5,200) It Runs Great Until You Hit A Good Sized Wake And Then The Rpms Rise And Fall Even With The Throttle Wide Open.and Then It Will Finally Fall To 3,000 Rpms And Stays There-it Is Running Smooth It Just Wont Get Above 3,000 Rpms.