Air Flow and the Fan Shroud
Air flow through the radiator and condenser is vital for engine cooling, air conditioning and heater performance. The fan shroud should be inspected and replaced if damaged. Don't discard this part if it is damaged or doesn't fit properly. The shroud and its accompanying air dams are responsible for between 10 to 30% of the system’s performance. Air shrouds and dams create low pressure behind the radiator and high pressure in front, drawing cool air through the condenser and radiator fins. A missing fan shroud could reduce cooling by a massive 50%. This part directs are flow, but also protects the fan and the technician working near it.
The fan shroud improves air flow at low speeds and idle. Many air dam systems in use today improve air flow at highway speeds as well. This air flow created by vehicle movement is considered ram air, because it's forced through the condenser and radiator by vehicle movement and speed. Check these parts to insure that they are installed and fastened correctly.