2nd Gen Non-Engine/Transmission Blend Door Stuck?

[CNichols]

Ok so this past winter I slowly noticed that I was getting less and less volume of air out of my vents on the dash. And now I only get a tiny bit out of them when the knob is on the "full dash" dash setting, and the rest seems to be blowing out the defrost vents. I played around with the knob this AM and I can get floor heat/AC or Defrost. Even when the knob is set on "recycle" where it used to blow extreamly well out the vents and vents only... seems to be directed out the Defrost vents with a tiny bit coming out the vents. Anyone ever run in to this? I would assume that a blend door is stuck but I dont even know where to start looking I hope its not deep in the dash somewhere :{



Thanks in advance for your help.







Charlie

 

[Joe G.]

Check the knob. I've had to replace the knob twice on my '95. It's plastic and can crack so it does not actually turn the shaft.

 

[CNichols]

I will have to look into that. Though im pretty sure the knob is still able to select all the settings. Did your knob "free wheel" when it broke? Mine still stops at the off position and such.





Thanks For your input

 

[Joe G.]

Mine seemed to be ok at first and got worse until it just slid around. When the 2nd knob failed I knew what was wrong so as soon as there was any funny business I got another one.

 

[CNichols]

Ok I will take a look tonight. Thanks for your help Joe.

 

[YEEHAW]

I've got the same problem, only mine happens intermittently and only seems to do it after a few minutes at cruise speeds (70-80). It doesn't do it around town. The last time it happened, I had my brother in the passenger seat and he tapped on a black cover under the dash just right of the heater vent on the passenger side. It slowly opened. So something is sticking in there. I haven't had a chance to tear it apart - well I keep forgetting about it - maybe I'll do it tonight. Thanks for reminding me.

 

[CNichols]

I will take a look at that also, i wonder if the vents and ducting and such are the same from a 97 vs. 99 as far as that goes.

 

[Dieselnerd]

The defrost is the default position when the system is at rest. When mine did that it was a diaphram leak that didn't allow the blend door to be pulled out of the defrost position. Others have had broken off or pinched vacuum lines and oil in the system. It's fairly easy to diagnose and fix most problems without taking the dash completely apart. Normally just removing the panel under the steering wheel gives you enough access to fix it.

 

[Missouri Mule]

Sounds like a vacuum problem to me!

 

[GAmes]

I just had that same problem a couple months ago and it was the diaphram in the actuator that had failed. Problem is the metal arm of the actuator that connects to the PLASTIC arm of the blend door doesn't come off easily. If you break the plastic part of the connection you have to remove the dash in order to replace the plastic arm that connects to the blend door. That turns a 15 minute job into a 3 or 4 hour exercise in frustration. I ended up bombing mine, so if the actuator fails again I won't have the same problem. If you are interested I'll try to give you the procedure, but it can't be done without removing the dash.

 

[Joe G.]

The '97 is different than my '95 if it has a vacuum actuator to open the door. So I withdraw my suggestion above. The '95 has a cable from the knob to the door. Too much strain on the cheap knob.



The dash will roll back if all you need to do is get to the top of the heater duct. Pull the driver's seat all the way back so it will clear the steering wheel. Lower the steering wheel. If you have an auto don't forget to remove the little cable that is used for the gear indicator. Loosen the two bolts below the ends of the dash. Remove all the screws in the dash just below the windshield. Then just lean it back. All the cables and other stuff can stay connected.

 

[GAmes]

Originally posted by Joe G.

Then just lean it back. All the cables and other stuff can stay connected.

Sorry Joe, not so. On the 97 the heat control cable is connected to a lever on top of the plenum assy and has to be disconnected in order to lower the dash all the way down. A b**** to get to if you are not too flexible, and a real b**** to reconnect.

 

[CNichols]

Originally posted by GAmes

I just had that same problem a couple months ago and it was the diaphram in the actuator that had failed. Problem is the metal arm of the actuator that connects to the PLASTIC arm of the blend door doesn't come off easily. If you break the plastic part of the connection you have to remove the dash in order to replace the plastic arm that connects to the blend door. That turns a 15 minute job into a 3 or 4 hour exercise in frustration. I ended up bombing mine, so if the actuator fails again I won't have the same problem. If you are interested I'll try to give you the procedure, but it can't be done without removing the dash.

Where is the actuator located?

 

[Cliffman]

Blend door does just what it says, it blends cold and hot air to achieve the desired temps. It has nothing to do with which vent your air is coming out of or the volume of air.

 

[Bob4x4]

The actuator is on the drivers side of the evap housing,near the accelerater pedal area.



Bob

 

[CNichols]

Thank you bob.

 

[Bob4x4]

Cliffman

He probably meant MODE door,just used the incorrect name



Bob

 

[Joe G.]

Originally posted by GAmes

Sorry Joe, not so. On the 97 the heat control cable is connected to a lever on top of the plenum assy and has to be disconnected in order to lower the dash all the way down. A b**** to get to if you are not too flexible, and a real b**** to reconnect. [/QUOTE



Wow! Just another reason I like my '95. I had a heater problem once. I had to lean the dash back several times before I get that to work right. It turned out to be a mouse nest.

 

[GAmes]

Originally posted by CNichols

Where is the actuator located?

First, I apologize for not doing the research before I typed a reply. The actuator I replaced is for the panel-defrost door, not the temp/blend door. If you have a manual it is page 24-34. As Bob states, it is above the throttle pedal and to the right. To test it start the engine and select dash vent with the control knob. Pull the vacuum line from the actuator and verify you have suction. Reinstall the line to the actuator. If the diaphram doesn't pull the lever in it has a hole in it. You can verify it also by manually pulling the arm in. If air comes out the dash vents then that is your culprit. Now the tricky and critical part. The arm is attached to a plastic arm that also doubles as the hinge for the door. If you pop that plastic arm out, as I learned the hard way, the door falls to the bottom of the plenum. I tried to remove the metal arm after removing the mounting screws. WRONG!!!! :{ The plastic protrusion is split down the center. Very carefully squeeze the two pieces together enough for the metal arm to slide off. Mine was very brittle and one of the plastic pieces broke off. Once you have the metal arm off, then remove the two mounting screws. If you have the misfortune of breaking the plastic as I did let me know and I'll tell you as best I can how I bombed the plastic lever. Gary

 

[Bob4x4]

If you turn the actuator to a diferent angle from installed position it will come off the plastic without breaking.



Bob