Blend Door Adjustment
Thread Starter
Drifting
Joined: Aug 2002
Posts: 1,775
Likes: 125
From: Birmingham AL
Blend Door Adjustment
I have finally completed the heater core installation in my '89. 
It seems that the blend door actuator might be out of adjustment as I can't get cold air from the vents. AC works and it's very cold outside. I guess that the blend door is not adjusted correctly. I did count the number of threads for reference when disconnecting and reconnecting the door rod to the actuator clip. 8 threads. I put it back as it was. Does this thing self adjust or is there a procedure? I did a search and found only this thread:
http://forums.corvetteforum.com/c4-t...ol-issues.html
I'll check the FSM tonight. I might also look inside the top of the box at the heat sink hole and try to see what's going on. Does anyone know of a procedure for this?
Thanks
It seems that the blend door actuator might be out of adjustment as I can't get cold air from the vents. AC works and it's very cold outside. I guess that the blend door is not adjusted correctly. I did count the number of threads for reference when disconnecting and reconnecting the door rod to the actuator clip. 8 threads. I put it back as it was. Does this thing self adjust or is there a procedure? I did a search and found only this thread:http://forums.corvetteforum.com/c4-t...ol-issues.html
I'll check the FSM tonight. I might also look inside the top of the box at the heat sink hole and try to see what's going on. Does anyone know of a procedure for this?
Thanks
Pro
Joined: Oct 2003
Posts: 550
Likes: 0
From: Hesperia California
On my 89, I don't remember threads. I thought it just slid hard on the rod. I think I left it long in the open position and cycled it a few times. When it closed, it slid to where it should be. Its been a while though!
Good luck!
Good luck!
Thread Starter
Drifting
Joined: Aug 2002
Posts: 1,775
Likes: 125
From: Birmingham AL
Thanks. I disconnected the battery again to let the system reset. I then reconnected and started the car. I did not touch the climate system and let it run through a reset, I suppose. I did not let it cycle the last time as my battery was marginal. I suppose that messed up the learn process. It seems to work a little better now. I guess that it learns the position. Nothing in the FSM about this.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Thanks. I disconnected the battery again to let the system reset. I then reconnected and started the car. I did not touch the climate system and let it run through a reset, I suppose. I did not let it cycle the last time as my battery was marginal. I suppose that messed up the learn process. It seems to work a little better now. I guess that it learns the position. Nothing in the FSM about this.
You might want to pull the passenger side hush panel/knee bolster to watch the actuator while working the AC/heater controls to see if your getting any movement from the actuator.
If you don't see any movement out of the actuator it is possible there is a problem with the actuator itself or another portion of the controls circuits of the AC system.
