HVAC help--the buzzzzzing dash Options

[Spooner]

I'm not sure where to post this, since it's an interior R&R question and not racing-related, so I figured I'd give it a shot here.

The HVAC fan in my car makes a huge racket/buzzing noise, as if it's hitting against something. Does anyone have tech on how to access and or dissasemble the fan so as to investigate such a noise? (All while taking as little of the dash apart as possible.)

It looks like the fan is on the passenger side, up underneath the glove box. I'm hoping that means it's not a total nightmare to access.

I searched and found a John D. thread to be very helpful in terms of visualizing the job. But I wasn't able to find anything that specifically addresses how to get at the fan in a full interior car.

I was happy ignoring the noise at first, but it's gotten progressively louder. Now I can't run it at all without it making a racket. Ugh....

Thanks in advance,

-John

[trackbird]

I have a service manual (Helm version), I can see what it says.

[John_D.]

There are 3 screws holding it to the heater box. Once you've taken the bottom panel off the dash you should be able to just push some wires out of the way and take the screws out, and the motor/fan will drop straight down.

Sometimes leaves/junk can get through the cowl and into the fresh air intake, which is right over the squirrel cage fan.

With the a/c switch set to max (recirculate), the fresh air flapper will flip over to pull inside air. Then you can reach in from the top and see if you feel anything stuffed in there.

(I'd unplug the fan first, so it's not spinning when you reach in...)

[CamaroFS34]

I'd venture to say your fan motor is about to die. Mine was doing that when I put it on high, and then about a week and a half ago, it just quit. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/sad.gif)

[Spooner]

Well, John, you had "squirrel cage" right. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif)

I just pulled it the motor down and the "cage" was full of at least a baker's dozen worth of acorns. After dinner, I'm going to put it back together and see what happens. I'm hoping that will solve it.

Karen, looks like a replacment fan motor is about $60 for the aftermarket version or $99 for the Delco unit from Rockauto. It would only take about 20 minutes to replace. (Unless there's a difference in the way it's mounted in a LS1 car versus and LTI car.)

-John

[John_D.]

That's funny. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/laugh.gif)

But no squirrels, right?!

The area behind the cowl is a big hollow area from one side of the car to the other. You may have more acorns rolling around in there, that will eventually make it down through about a 4x6 hole in the floor of that hollow area, that feeds directly down into the blower. So you may have to do it another time or two until they all make their way down there...

[Spooner]

That's funny. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/laugh.gif)

But no squirrels, right?!

The area behind the cowl is a big hollow area from one side of the car to the other. You may have more acorns rolling around in there, that will eventually make it down through about a 4x6 hole in the floor of that hollow area, that feeds directly down into the blower. So you may have to do it another time or two until they all make their way down there...

Nope. No squirrels. And no more buzzzz. (Phew!)

It'll be interesting to see if there is more junk in the hollow. I have an autocross next weekend. That might shake them loose.

For those interested, the detailed instructions to R&R blower motor/fan (at least for a 99 LS1 car) are:

Step 1: remove glove box
-remove three small (7mm) hex head screws located just in front of the glove box hinge. They're accessible from underneath. Don't have to open the box to get at them.
Step 2: remove bottom dash panel
-remove two plastic push pins on either corner
-remove clip at back left corner, pull panel forward
Step 3: remove blower motor/squirrel cage
-unplug wire harness (easy to spot, right in front of you)
-unscrew three 7 mm hex head screws
-unit drops straight down

also:
-be careful because the small screws for both the glove and the blower motor go into fairly brittle plastic. Don't tighten them with a lot of force or you could strip the holes.
-removing the passenger kick panel as well would afford a little more room to maneuver. I chose not to bother, though.