AC blows warm at idle – F150
Ford has issued a service bulletin 07-24-7 to address an AC blows warm at idle issue on 2007-2008 F-150, F-150 and 2007-2008 Lincoln Mark LT vehicles with the 4.6L and 5.4L engines.
Ford has programmed the AC systems in these vehicles to shut down the compressor in high ambient temperature conditions (>110F) and when the vehicle is stationary for longer than 15-mins. while in gear. Ford does this to prevent compressor overheating. This AC blows warm at idle can happen while you’re waiting for a train to pass or if you’re stuck in bumper to bumper traffic. One option is to place the transmission in PARK. The PCM will then increase engine cooling and get more air across the condenser. Ford also recommends setting the AC to the MAX position and reducing the blower fan speed. That’ll lower the temp of the air coming out of the ducts.
Ford also recommends replacing the AC compressor pulley, coolant pump pulley, and the clamp on the heater core feed hose located near the right hand front of the engine at the water pump outlet. The new parts are listed below:
Compressor Pulley . . 7C3Z-19D784-A
Water Pump Pulley . . . F6TZ-8509-AA
Hose Clamp . . . . . . . . W709811-S900