So I have a 90 na and when I start the car to go anywhere it had very poor throttle response . Only while it's sitting still does this happen . If u tap the gas as if you were pulling away it hesitates very badly . Now when I'm driving the car it seems to run fine . It doesn't skip or hesitate . What could this be? Where should I start. The car is basically stock . Only mod is cat delete . Still has factory muffler and exhaust. Help please