when i choke with the solenoid, the valves slam shut and then fall back open a little. it looks like the plastic piece coming out the bottom of the solenoid where it hooks to the linkage has a little bit of slop in it causing this to happen. is that normal or something i can adjust out by adjusting the solenoid rod? i'm almost to the end of the travel for adjustment already, (about 1/16in or a little more threads still showing on the rod.) any ideas?