Weird high pitched noise??

[digadt]

Yea i have a 99 3.5 intrigue. ive had the car for almost 3 years and it has 85,000 miles on it . since about a year ago ive been having this problem. it seems like only when i put my heat on. i get this really high pitched screetching noise from wat sounds like the fan. has anyone else had this. do u think it may be a some sort of build up of dirt or dust or something? also on a different problem when i have it in drive and im at a stop i feel heavy vibrations from by my feet. my mechanic says it may b the engine mounts. wat do u think? does anyone else have these problems?? please help
thanks

[panzer dragoon]

the high pitch whine is your blower (heat/AC fan) motor. = The whine pitch should go higher with an increase in blower (fan) speed. The fan bearing got corroded from moisture (a problem with the Intrigue) and also from general wear and tear. Did you burn out any of the fan speed settings yet? = eventually the higher current use of the fan will melt the resistors used to control the fan speeds.

http://www.automotiveforums.com/vbul...d.php?t=671765

The pitch should change with a change of the blower motor speed. If it does not = most likely something else. The noise may only be noticeable on high speed right now, but eventually it will get worse.

You need to look into unplugging the AC moisture vent also. =This may be plugged causing the bearing to fail early from excess moisture.

[digadt]

ill look into that....i just had my blower motor replaced and its still making that noise even as soon as i turn the heater on ..so by the way you explained it means that its pretty corroded. unplugging the ac moisture vent alone wouldnt help the noise?

[panzer dragoon]

http://www.automotiveforums.com/vbul...hlight=ac+vent

unplugging the AC moisture duct (vent) would definately help your fan longitivity in the future. Do a search for "AC vent" on this forum. I was wrong -they say the noise is more prevalent at low fan speeds. =I had the problem on my 1975 Olds = that was a long time ago.

If the noise goes up with engine rpm = it's not the blower motor. Maybe a squeeky engine belt or bearing somewhere.

[atoyota4x4]

On that vibration around your feet while stopped..... Well, my lower motor mount broke and gave me that exact same feeling/sound. I was hesitant to believe that was my problem, but it was. Sadly, it about a $400 repair if you have a shop do it.