At this point they are considered incertae sedis;in other words, we know that they are theropods; and probably coelurosaurs; but we don't know who they are related to or how they fit into the big picture of theropod phylogeny.
Idle speed is adjusted by means of the idle control valve, which is a solenoid-operated valve that is generally automatically adjusted by a computer. One problem that can occur with this component is a loss of power (from a severed line or a short) but a more common problem is simply dirt and grime.
Pilot valves are valves which are used to control other valves. Pilot valves in the actuator lines control the supply of air or liquid going to the actuators. The fill valve in a toilet water tank is a liquid level-actuated valve. When a high water level is reached, a mechanism shuts the valve which fills the tank.