2004 LeSabre 49K, medium-pitched whirring sound at idle.

[tcpalmertw]

Recent car purchase, and I am relatively unfamiliar with front wheel drive nuances that may be found with the 3800. There is a "come and go" medium pitched whirring type of sound coming from the engine compartment that can be heard through the firewall at idle and higher RPM's in neutral. This noise is lower pitched than the alternator. This noise may stop if engine is turned off and re-started. It would seem to be a bearing type of sound, but is quiet enough to be somewhat concealed in terms of source. Here is a key: When engaging any of the power window motors or power seat when the window or seat is at its limit, the sound goes away for about a second. Also, you can hear this noise when coasting in gear but seems to go away when you give it a little gas. Does this indicate pulley bearing, as it is affected by the alternator load change, and if so, which pulley is most likely to be the culprit, or is the cause of this sound something else? Has anyone else experienced this? Mechanics seem to be baffled. Many, Many Thanks in advance for any help! Tom from East Texas

 

[IMSITINGINYOURCHAIR]

The belt tensioner pulley could be the culprit. You really need to use a to isolate the source. Check your ac compressor as well. they have problems with failed bearings.

 

[DonP]

Sounds like it changes with load on the belt. You have the alternator, power steering, water pump, tensioner idler, belt idler, A/C compressor and crank shaft pulley to consider. A mechanics stethoscope might help pin it down. You can sort of improvise with a piece of tubing, but be very careful of the moving belt.

Does the A/C state (on/off) make a difference (if it is warm enough where you are to turn on the A/C)? How about state of the steering wheel (e.g. hard over or in motion.)?

Water pumps and alternators are arguably the most common to have bearing problems, but they do not have a lock on that issue. The P/S pump is in an out of the way location and that could be masking it as the source.

Maybe try remove the belt and turn each pulley by hand carefully feeling for an excessive play or other abnormal feel/sound. Also check the condition of the belt for fraying that migth cause nosie under changed tension conditions.

 

[1380Ken]

Probably not good advice but I would ignor the noise and hope that it went away.

 

[gnhbodyguy]

My 1998 has been making a noise from something for all the 14 years I've owned it. It sounds a bit like a smaller tin can (say mushroom sized) spinning around in another tin can. It is usually worse right after start up. I've never replaced anything powered by the drive belt. All original after 160,000 miles.

 

[redmondjp]

I don't know that I would worry about it too much either; my 2001 has similar sounds at times and I've never pursued them.

My MIL's 2003 Century also makes a whirring noise (almost sounds like whistling) that I think is coming from inside the transmission, and it seems none the worse for wear (over 200K trouble-free miles on it now).

I'd guess that it is the alternator - if you're really concerned, remove the serpentine belt and spin all the accessories by hand to see if they turn free, smooth, and quiet.

 

[beautgsx]

I purchased my 2004 Custom a few months ago. Now at 65K, I'm having the same issue for a few weeks now. It started out very minimal, but now it happens every day. You may not even own the vehicle anymore, but if you do, did you ever get it resolved? Any help would be greatly appreciated!

 

[gnhbodyguy]

Try a can of A/C system oil.

 

[beautgsx]

I just saw your response. The noise quit for a while but is back again. I'll give it a whirl.