Driver side blows warm and passenger side much cooler (1 Viewer)

[-MaTTi-]

What’s wrong? Left side blows warm good enough, but at the same time right side blows almost cold. I can feel at the center vents too, the left side blows hotter than right. The blow is about the same.

I checked the cabin air filter, it’s good. The air flow selector works, aiming changes like supposed. Coolant level is ok, AC works ok.

 

[jellyroll]

Haven’t had it happen in my fj, but it sounds like the same thing that happens in my dodge pickup. There’s a flap that opens & closes allowing the direction of heat or cooling. Either the rotating actuator stops working or the connection point on the flap breaks disabling the correct function option.
Is it blowing at the same velocity on both sides?
At least you have heat on the drivers side, mine will cook the passenger while I freeze my butt off driving

 

[BMThiker]

Man, I don't envy the exploratory work this may involve. Taking the whole dash apart is quite the endeavor.

 

[-MaTTi-]

There’s a flap that opens & closes allowing the direction of heat or cooling. Either the rotating actuator stops working or the connection point on the flap breaks disabling the correct function option.
Is it blowing at the same velocity on both sides?

Yes, but isn’t that flap affect both sides at the same time?

The velocity is slower in passengers side, still good enough.

Maybe the heater core is glogged? I don’t know how it would be possible, I have used nice pink coolant all the time.
Here is the same problem solved: Hot air driver side and passenger side cooler

 

[BMThiker]

Just spitballing, but maybe the air ducts on the passenger side are exposed to more fresh air being so close to the intake/cabin filter assembly? Could try wrapping those ducts with insulating mat.

 

[jellyroll]

Yes, but isn’t that flap affect both sides at the same time?

Good point, I did think of that immediately after posting my response.
Slower in passages side, maybe a critter in there? We had a mouse nest in the cabin filter once, although we never noticed any difference.