2003 Discovery, 70K: Every time I turn on the heater (esp. on automatic) there is a chirping whistling noise eminating from the blower vents underneath the dash. Perhaps a wire rubbing against a fan? And how involved is it to fix it myself? It comes and goes, the noise does.
Thanks all!
KL

 

Bad bearings in the HVAC fan.
Turn the HVAC on and then adjust the fan speed manually and see if the noise increases/decreases with the fan speed.

 

It is intermittent. If I take the fan off "automatic" and run the fan speed as fast as it can (high), it seems to go away. But a big bump or railroad tracks will bring the sound back (and even sometimes take it away), but it always returns, intermittently.

 

I have the same exact thing...

 

Bad HVAC blower.
Run it until it seizes but in the mean time buy another and have it on hand, it may last years this way or it might go out tomorrow.

 

I agree with Spike's advise, other than you may just want to find a place that has one readily available (one day away) rather than buying one for * "if/when" *. 2 years ago, my blower motor started making noise, not really a bearing noise, but more like either like something hitting the fan, or a brush in the motor. I knew I could get a new one through WorldPac in one day, so I waited until it failed. It never did, and the sound went away completely after a few weeks, and has been fine for 18 months.

*mine might be a special case, and this is one of the few things I would recommend holding off on replacing until it fails, rather than preemptively a potentially failing part (like front drive shaft u-joints).

 

Pull the blower motor out, you may find it is just packed full of trash it has sucked in.

 

sounds like youve got a whistling bird in your vent!

 

How difficult are they to remove?