Got to within 20k of an asteroid with 700 m/s of delta V thought wow nice should be no problem, WRONG. the autopilot kept doing flybys wasting dV because it wasn't figuring in the slow rate at which the vessel turned.

• Open the attitude adjustment window and increase Maximum Relative Angular Velocity. (be warned: higher values are less propellant friendly)
• Also make sure your craft HAS sufficient control authority to make the maneuvers demanded of it.