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WTH is this knock in the dash? '09

Jonk67

Well-Known Member
Ok, I'm stumped, wife comes in and says her car knocks before she starts it. '09 V6 and I thought maybe the battery was going out and the solenoid was clicking but no. It is a solid loud knock and you can feel it at the center of the dash when you turn the key on before start. Tried it with the air controls on and off, same result.
Attached a video that is 30 seconds, first try with AC on, 2nd try with it off and then with my hand at the center of the dash to feel the knock. Is it some kind of servo that is sticking or ???? About 10 quick knocks and then it stops.

http://s194.photobucket.com/user/jkoed/media/2009%20WIP%20Mustang/Repairs/DSCN3043_zps108e1986.mp4.html

Jon
 

AzPete

Well-Known Member
Does the vent selection work properly with the heat and a/c. Fords default to the defroster when any servo goes bad. It sounds like that is what yours is starting to do. It also could be a vacuum leak causing the doors not to function properly.
 

Jonk67

Well-Known Member
Thanks Pete, I'll have to test that. I got a similar reply on a late model forum - common, vent door actuator failing, ~$30-$40 at ford, more than one and some are easier to get to through the glovebox. I can only hope it's an easy one as the car is out of warranty, about $400 if the dealer does it I'm reading.
Jon
 

Jonk67

Well-Known Member
Sure sounds like it doesn't it. Looks like it may control the blend doors, since we hit 20* this morning I have a feeling the wife's going to want heat and I'm going to hear about it....
Jon
 

Jonk67

Well-Known Member
Well, I got it out and verified it's the bad one by unplugging it, opened it up and one of the gears has teeth missing. Now I'm trying to figure out how to identify which one it is as there are two that are similar. Since I accessed this one from the glovebox and it's the highest one up I'm hoping it's the defroster one.

Upper one:


Removed:


Opened up:


Jon
 
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