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  #1  
Old January 27th, 2010, 04:08
mhopton mhopton is offline
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Blower's blowing, but's not blowing....huh?

OK, have searched and read and have narrowed this down.

- It isn't the blend door - I have very cold, or very hot air - when it's blowing.
- It isn't a vacuum leak - I have air blowing at all of the correct positions, feet, vents, defrotst, etc, when dial is turned.

Essentially, sometimes, when the fan speed is on 1, or 2, or 3, or even 4, I get very little air movement. I can hear the blower blowing like crazy up/down as the fan speed dial moves about, but sometimes, just no air.

Can this be narrowed down to the heater resistor under the dash on the passenger's side? Or, something else?

It *seems* to get better when I flip the temp control from hot to cold, but I'm not for sure.

BTW, 99, auto, 4.0l, 4x4, 90k. All stock.

thanks
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Old January 27th, 2010, 06:28
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winterbeater winterbeater is offline
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Re: Blower's blowing, but's not blowing....huh?

The resistor just makes the fan speed change. And is completely bypassed on high speed. Don't know why fan would make a lot of noise like it is blowing, but air not come out anywhere.
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  #3  
Old January 27th, 2010, 22:32
lawsoncl lawsoncl is offline
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Re: Blower's blowing, but's not blowing....huh?

Is it coming out the wrong vents, like the defroster or floor instead of where you are expecting?
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Old January 28th, 2010, 04:03
mhopton mhopton is offline
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Re: Blower's blowing, but's not blowing....huh?

No, coming out all the correct places, which I'm sure eliminates a vacuum leak. Just minimal blow at each fan setting. High works well though, which is why I think it may be the resistor at the passenger side foot well.
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Old January 28th, 2010, 04:59
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Re: Blower's blowing, but's not blowing....huh?

For a bad resistor block, the blower motor will generally work only full blast/high. Turning the switch through the different settings will make NO difference.
If that is the case, suspect the resistor block.

With minimum output at the lower fan settings, your problem may be the switch itself

But if the blower motor rpms go up and down as you move the heater switch, but air movement/output itself varies, I think I'd start looking at the blower motor.
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Old January 28th, 2010, 06:27
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Re: Blower's blowing, but's not blowing....huh?

But blower volume must be directly related to blower rpms unless the "squirrel cage" is spinning on the motor shaft or blocked by something. And if it spun on the shaft much, it would bind up pretty quick.

And the resistor either works or it doesn't. The thermal fuse blows out and takes out all speeds but high.
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Old January 28th, 2010, 07:16
Irbys19 Irbys19 is offline
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Re: Blower's blowing, but's not blowing....huh?

I agree with the previous post i wave seen the blower wheel strip out on the shaft of the blower motor and not want to spin but if thats the case it will eventually stop working.
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Old January 28th, 2010, 07:32
skywalkr skywalkr is offline
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Re: Blower's blowing, but's not blowing....huh?

Quote:
Originally Posted by lawsoncl View Post
Is it coming out the wrong vents, like the defroster or floor instead of where you are expecting?
not to hijack this thread or anything , but I have this problem as well and the air does come out of the wrong vents...I'm thinking its a vacuum leak but am open to suggestion...
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Old January 28th, 2010, 08:03
kastein kastein is offline
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Re: Blower's blowing, but's not blowing....huh?

Probably a vacuum leak or one of the air doors came disconnected from a cable actuator.

As for the OP's problem... maybe something stuck in the ducts blocking the airflow? Maybe the motor shaft stripped out of the blower fan? Maybe the blower motor is actually going really slow, but the brushes are grinding or the windings are humming angrily due to overcurrent from the motor going slow, and it sounds like it's going really fast?
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Old January 28th, 2010, 10:03
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Re: Blower's blowing, but's not blowing....huh?

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Originally Posted by skywalkr View Post
not to hijack this thread or anything , but I have this problem as well and the air does come out of the wrong vents...I'm thinking its a vacuum leak but am open to suggestion...
Default mode is defrost. So with no vacuum, you get defrost. With too little vacuum, you might change to defrost under heavier acceleration.
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  #11  
Old January 28th, 2010, 15:02
skywalkr skywalkr is offline
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Re: Blower's blowing, but's not blowing....huh?

Quote:
Originally Posted by winterbeater View Post
Default mode is defrost. So with no vacuum, you get defrost. With too little vacuum, you might change to defrost under heavier acceleration.
that is helpful as it will always work on defrost but nothing else...
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  #12  
Old January 29th, 2010, 05:46
mhopton mhopton is offline
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Re: Blower's blowing, but's not blowing....huh?

Thanks for the posts and information. I'll pull the resistor and check it but it sounds like maybe I just need to swap out the blower motor. The output is in all the correct places and at the correct temp, it just doesn't...well, put out. We all know that is NO good!!
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Old July 18th, 2010, 19:00
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Re: Blower's blowing, but's not blowing....huh?

What did the problem turn out to be? I am having the same symptoms.
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Old July 18th, 2010, 19:48
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Re: Blower's blowing, but's not blowing....huh?

I fixed one where the squirrel cage was spinning on the motor shaft.
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Old July 18th, 2010, 19:53
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Re: Blower's blowing, but's not blowing....huh?

Quote:
Originally Posted by old_man View Post
I fixed one where the squirrel cage was spinning on the motor shaft.

X2^^ motor spun like a champ, but no airflow-- fan was stuck and the motor was "freewheeling" in the fan mount.
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