Drivers side air vent flow issue

[93z]

Does anyone have an idea on what would affect the driver side AC vent air speed before I tear into the dashboard?

Most of the time the speed of air coming out of the driver side dash vent is very slow. About 10% of the time it will flow full speed for about an hour and then I hear an actuator move behind the dash and the flow is cut down to about quarter speed again. Other vents speed may be affected as well but I noticed the driver side most.

I have disconnected and played with the driver side actuator near the gas pettle and it makes no change. I have inspected the fresh/recutculating actuator above the blower fan and that seems to be functioning normal. The only one I have not played with is the AC/heat blend door actuator.

93 FZJ80L
R12 converted to R134a

Thanks

 

[voodu3]

This might be a stupid question but does your 93 have climate control? The auto button in the center of the AC controls. I assume this would control the fan speed speed once the temp was reached.

 

[93z]

It has manual AC. No auto button.

 

[Kernal]

Does this happen (un-commanded change in air flow) when the HVAC controls are set to a different position, or just for a specific button/selection?

 

[93z]

I run it -
Temp slider all the way to cold
Fan speed high or medium-high

No changes are made to the controls when the air speed drops.

I am not sure if it happens in a certain setting combo. When airflow is reduced you can change all the settings and nothing will bring it back to full speed. Even turning it off and waiting a bit or overnight.

It is ice cold when the fan is blowing fast. I have replaced every non electrical component of the AC including the expansion valve. Filled it by weight with proper gauges. High and low pressures look good.