Defrost flap actuator 1989 c4
Thread Starter
8th Gear
Joined: Jul 2024
Posts: 8
Likes: 0
Defrost flap actuator 1989 c4
I am restoring a 1989 C4 at the request of grandson. The defrost flap pneumatic actuator is not working. I am atemping to remove it after testing it. I do have the dash, instrument panel, and drivers side footwell (under dash) pretty much disassembled. I have the actuator disconnected from its brackets. However, I cannot get it to drop down for removal from underneath. It appear that I could remove it from above if I could remove the drivers side ventilation duct. I do believe I have all the screws removed, but I cannot remove the duct.
What is the procedure for removing the actuator?
What is the procedure for removing the actuator?
Drifting
Joined: Sep 2022
Posts: 1,512
Likes: 401
From: Liberty, SC
2023 C4 of the Year Finalist - Unmodified
You're a bit down the rabbit hole now but you should have been able to reach thru and move the flapper by hand once you took the upper vents off. What happened then that made you want to remove it entirely? was it stuck or broken somehow? I'm mostly curious - I can't think of what could go wrong with it.
Last edited by 2011KLR; Jan 5, 2026 at 08:38 AM. Reason: i didnt like my first reply....
Drifting
Joined: Jan 2021
Posts: 1,315
Likes: 385
From: Northern California
To the point of @2011KLR above, you should check out the vacuum line and/or HVAC Programmer module first. If you've got most of the driver side lower dash already disassembled, the module is right there above the accelerator pedal area. It, and the vacuum line hose, are the more likely points of failure. Run the diagnostics from the FSM to be sure. Good luck.
