Heater Fan Noise

Hello,

I've got an '02 Trailblazer that is having an intermittent problem with its heater/AC fan. If I run the AC at its coolest setting for a while with the fan set to high, I start to hear a noise from within the dash. It sounds like something is rubbing against the fan's blades. The frequency of the sound goes up and down with the fan speed. Funny thing is that it does not happen all the time. Any ideas?

Thanks

My 2002 TB had the same problem. Turned out to be a broken blower impeller. Possibly something fell down the defroster, but either way you will have to get into the blower to find out.

From Alldata: (sorry, couldn't paste a pic)

Remove the right closeout/insulator panel.
Remove the I/P storage compartment door.
Disconnect the blower motor electrical connector.
Remove the blower motor mounting screws.
Remove the blower motor cooling tube.
Remove the blower motor (2).

Have fun...

Thanks for the info JFletch! It hasn't happened again, but if it does, I'll definitely put what you've suggested into action.