There is a door actuator (motor) that the gears are stripped, when you shut the
key off the motor is looking for home position.
Enter the truck from the passenger door and look under the dash you will see
the black box for the blower assembly, that is where the sound is coming from.
Sorry I can't get more specific but it has been a couple of years since I last
worked on a 94 with that problem so I can't remember how to describe for you
where to look.
I do know the actuator is a PITA to replace.
It is about the size of a pack of smokes and I think it had three wires going
loud knocking sound that is comming from the air distributor box on the
passenger's side of the cab. The sound only lasts about ten or so seconds
while the louver in the box is being sucked closed. Has anyone else had this
problem? If so, what was the fix? Thanks,G-
Live to learn with the noise! It's a huge PITA to get at and not worth the
time. Mine's been doing it for YEARS.
Live to learn... hehehe.... I do but I don't think thats what you mean?
-The Lonely Grease Monkey
1985' K5 305CUI TH700R4 NP208
"Ignorance is preferable to error; and he is less remote
from the truth who believes nothing, then he who believes
what is a wrong."
- Thomas Jefferson
Hey guys, thanks for the advice. I ended up pricing the part #16141802 at the
local Chevy dealer at $51.00 Ouch! So I did what I thought any tight as**d
ba***d would do and I unpluged the dumb thing. Now when I turn the key I don't
get any knocking. Of corse I also don't get hot air on the pasenger side floor.
But that was the trade off for not being willing to spend the money on a new
part. Thanks, Glen
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