#4. 2.0 LITER PLUG-IN HYBRID. Hose assy. LEFT. PartQualifier: #4. Flexible Hose that is part of the engine cooling system. Heat Exchanger. HVAC Heater Hose. and Amplifier; tube Assembly. Connector tube. Cooling pipe. Elbow. HVAC Heater. Outer. Radiator Coolant. Water inlet. Water Outlet.