Power Liftgate Won't Open Automatically

[metatr0n]

We've got a mint 2008 MKX AWD w/ ~82k on the odometer. We love the car, save for one minor issue: The Power Liftgate rarely, if ever, opens (or closes) automatically. I have tried the various reset methods mentioned in other threads to no avail.

 

If it helps, I can post a video later, but here's what happens in the two possible scenarios:

• Liftgate closed: pushing the key fob button twice or the button below the instrument panel causes the lock to actuate but the Liftgate never opens automatically. There is the familiar *ding* *ding* *ding* sound that appears to be emitted from the rear of the vehicle. When I grab the Liftgate handle, press the button on the underside and lift the gate, there is considerable resistance and it doesn't seem to want to "pop" open. There are no noises that would make me think the actuator assembly is binding, it's just hard to pull open.
• Liftgate opened: pushing the key fob button twice or the button below the instrument panel causes the lock to actuate but the Liftgate never closes automatically. There is the familiar *ding* *ding* *ding* sound that appears to be emitted from the rear of the vehicle. When I attempt to close the Liftgate manually, the resistance "feels" normal and is fairly easy to close.

To put it simply...

1. I push a button to open or close the Liftgate
2. The lock on the Liftgate actuates
3. I hear a series of *ding* sounds (I believe 3 or 4)
4. The Liftgate doesn't move at all

I suspect (hopefully) that the struts are just trashed and should be replaced. What complicates the problem is that 2 out of 5 times, the door will open and close just fine, and sadly I never remember to make note of the conditions during the times that it does work. If it were truly the struts, I would expect them to perform poorly in extremely hot or cold temperatures (it's 100 every day here in Austin at the time of this post).

 

Any other ideas? As I've said, I tried the various Liftgate reset procedures with no improvement. The car is obviously out of warranty and I'm hopeful that the motor/actuator that powers the Liftgate isn't toast.

 

Thanks in advance!

Edited August 28, 2014 by metatr0n