When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey I have a 97 supercab 4x4 4.6. Recently my ac compressor went and instead of replacing it I put a "dummy" pulley in its place. I thought the vent would still blow in cool air from the outside. However, when the truck is warmed up it blows really hot air out of the vents on the coolest setting. even if its 50-60 degrees out it still blows really hot air. Am I missing something here?
Outside air only works in PANEL and FLOOR with the temp control all the way to cooler setting.
If your getting very hot air, the air control flap is not working to divert outside air into the Panel or Floor selection. That means the heater core is being allowed to feed the panel or floor selection.
All other selector functions normally call for the compressor to operate.
Good luck.
Outside air is selected in ALL positions EXCEPT Max A/C and OFF. See the inlet air vacuum motor truth chart in the service manual.
Your temperature blend door is either inoperative or is not properly sealing when in the position for coldest airflow. Check the FAQs in the HVAC forum.