I know of a couple of problems these supercharged motors have. Either of them would cause a skip. One would be a fuel injector, the other would be a leaking intake manifold gasket. When it warms up and starts skipping, (if it skips at idle) spray some carb cleaner around where the intake manifold bolts to the cylinder heads. If this causes the motor to "perk up", then you've got a bad intake gasket. If it'* a bad injector, one cylinder will run lean, and you should notice that by looking at the spark plug. If you have the intake manifold gasket replaced, change the oil within a couple of days of having that work done. Many shops aren't very careful and I've had to replace several motors because they "spun a main bearing) immediately after having the intake gasket replaced because they allowed trash and metal slivers from using a wire brush to clean the old gasket off.