I own a 1990 F150 XLT Lariat with 207k miles. 300CI 6 cylinder in line. It has been the best vehicle I have ever owned. I have a problem with the blower and or air volume. Over the years, the volume of air coming through the floor vents, defroster and panel vents has been diminishing. The air blows very hot through all of the vents, the problem is that there is hardly any volume of air flowing through the vents. I know when the truck was new, the air volume was pretty impressive. Can anyone tell me what the problem is ? I appreciate any help.

thanks

JR

 

I would recommend that you remove the blower motor and check for debris in the heater box assembly. Older Fords were notorious for this.

 

I pulled the blower motor off and found just a very small amount of leaves in the box. They were at the base of the "a" coil or airconditioner coil. Could this be enough to restrict the airflow?

TIA

 

I think your 1990 f 150 is cable operated, if the cable bines up inside it case it might not close the door all the way, this would accout for the amount of air being different (not as strong) I have a 88 and was able to reach up with my hand and move the door manually, I had a broken cable though.

 

I have seen this problem on work trucks or trucks that collect pet hair. If the system is run on recirculate it picks up air from under the dash on the passenger side. What I have seen is the evap core getting plugged with pet hair and or dirt/debris that is picked up from inside the vehicle thus restricting air flow. The fix was to replace the evap core. Not fun to do. Hopefully this isn't your issue. But I thought I'd share my insight.