HVAC blend door actuator

CowboyTJ

Member
Joined
Oct 3, 2021
Messages
72
Location
The South Coast of Mississippi
Hello everyone, this is my first post. If this topic has been discussed, I could not find it.
Weak air flow and appears to be coming from all vents.
All actuators are moving but air flow is weak. Maybe the arm that the actuator moves is broken. I have heard of putting a screw into the plastic arm to avoid replacing the doors in the box. Can anyone give detailed instructions on which actuator to put the screw into and how? My problem is everything works but blend doors are not moving properly.
I can get my hand in there but don't know where to put the screw or if that even works.
Thanks
 
I agree with Pagrey....
Before assuming there is a problem with the door actuators, verify the speed control selector and motor resistor are working properly.
IF they are putting out the proper voltages; then remove the fan motor and inspect to ensure the motor is speeds are working properly.
 
OK, I should have started by giving more info. It's a 1999 TJ Sport 4.0
AC and heat worked perfectly and one day, no blower. After a little research I bench tested the blower, replaced fan speed switch, temp control switch, mode switch and resistor all together. All speeds worked, BUT.
Air flow is weak through all vents at the same time. As far as I can tell there are three vacuum actuators on driver side, and one vacuum, and one electric on passenger side. Passenger side vacuum operates the interior/exterior air source, electric one works heat/ac door. (I think) After removing the elect. motor I can see it move and I can work it by hand and hear the door close from side to side.
Not exactly sure about function of the 3 on driver side...meaning which one does what. But they all work, or should I say they all function. I can see the actuator moving the arm that should move the door inside.

I guess my question is, does anyone here know which actuator I should be trying to fix and is there a way to do it without disassembling the dash and removing the HVAC box?
Somewhere while researching all of this I saw a video of a guy put a screw into the plastic arm of one the actuators and he said it worked. I have not been able to find it again. I am hoping someone here has seen it done or tried it and does it work?

Thanks