You shouldn't smoke a tenderloin low and slow as you would a pork butt or shoulder. It's too lean to survive.
Soak the chips in water for a half hour or so then wrap in foil to make a completely closed package. Poke a few holes in the top of the bag.
Preheat the grill and place the foil packet on the lava rocks/flavorizer bars/or whatever is below the cooking surface and directly above a burner .
When the smoke starts, adjust the grill to a roasting temperature and put the tenderloin on the grill. Turn off one of the burners and place the tenderloin above the OFF burner. This is cooking by indirect heat which will take a little longer and allow smoke to flavor the meat.