90 C4 heater air door valve motor not working.
 

Any input would be appreciated. The heater will not blow any warm air and I suspect that there is a malfunction with the air door motor as I hear a noise like ZZZZZZZZZZZZ ZZZZZZZZZZZZZ. Sounds like motor is trying to move door but it won't. Any way to know if door is actually moving or not? Thank YOU.

RE: 90 C4 heater air door valve motor not working.
 

Hey, i had the same problem in my 94. If the setup is the same, then the problem is that your Vent Door Actuator has either seized or that a vaccuum line has been Disconnected. It is probably seized though. The part itself is $50 so it isnt that bad. The process isnt all that easy, but it CAN be done by yourself. I tried to take mine to PEPBOYS and they tried to tell me it would be almost $800 with parts and labor. I took it to a friend of mine and he did it for $100. You have to take off the Passenger side-lower dashboard. There is alot involved with taking it off. Then, once you get to it, you have to locate the Vent Door Actuator and once you find it, you have to disconnect it and put in the new one and reverse the process. I dont think there is really any more detail than that but i would make sure that you mark everything you take off as you go so that you know where to put it back. Good luck!

Matt

RE: 90 C4 heater air door valve motor not working.
 

Actually, its not the vent actuator, but the blend door actuator. The vent or mode actuator controls which direction the air blows, not the temp. :D

RE: 90 C4 heater air door valve motor not working.
 

Hmmm... well i replaced my vent door actuator because i had the same problem with it not blowing any hot air and it worked fine... Might the year have something to do with it? I DO know that the part i bought was called VENT door actuator. Anyway, good luck lol.

RE: 90 C4 heater air door valve motor not working.
 

Thank You to 94BlackC4 and mech259 for your input. I carefully ( and bravely I might add) took the dash apart exposing mostly the passenger side of the dash. I saw what looked like the heater housing but saw no sign of the blend air door actuator. Do I have to actually try and remove the heater unit itself. I hope not as i don't think it was made to come out?

RE: 90 C4 heater air door valve motor not working.
 

I will check on it today on Alldata and see. [8D]

RE: 90 C4 heater air door valve motor not working.
 

Hey mech259, any luck looking in Alldata for more info on removing the heater vent blend door?

RE: 90 C4 heater air door valve motor not working.
 

Sorry, it was a very busy day today and I forgot about it. I will try again tomorrow. :eek:

RE: 90 C4 heater air door valve motor not working.
 

mech259, Thank You for taking the time to look this info up for me. I appreciate it very much because in my little town there is no one to ask for help.

RE: 90 C4 heater air door valve motor not working.
 

Hey JeffM7344or mech259,

I know it's been a while, but what was the fix? It sounds like I've got a very similar.My air mix door won't go to heat, unless I unplug the mix door positionfeedback signal wire. I checkedthe signal wireand the voltage is varying as the door moves. The door will go full heat/coldfine until I plugtheposition feedback wireback in. But when I plug it in, it's as if the controller gets confused; the door goes back to full cold, but thenstarts going back and forth. I know it sounds like I need a new a/c heat controller, but I'd like to know for sure before I spend who-knows-how-much. Thanks.