3.4L 2002 LS

Ok guys I have a problem. My monte started getting a sqeaky belt noise in what seemed to be the water pump area. So I replaced the water pump, but the noise came back after the car ran for a couple of minutes. When I first started it, it wasn't doing it. Upon further observation I noticed the crankshaft pulley seems sort of wobbly, but smooths out when you rev it up a little.

So I sprayed some belt conditioner on the belt to see if it would help, and it did but it revealed something else. The squeak went away, but now it has a horrible whirring noise.. like something is trying to lock up or has a bad bearing.. or a failing pump. So I took the serp belt loose and spun all the pulleys by hand (except the crankshaft, of course), and none of them seem to have any abnormal resistance to them.

I'm kind of stumped here. The noise still seems to be coming from the area near the water pump / power steering pump / tensioner pulley. How should I proceed in my troubleshooting to figure this out without throwing parts at it?

 

PCV valve can cause this sound. As can the alt and the ps pump. Use the screwdriver to ear trick and see if sound like its the alternator bearings. (I had a bad pcv valve and alternator bearings going bad) fixed valve not alternator.

 

Heres a quick Tip:

Get a bottle of water with a squirt nozzle.. (like a window cleaner bottle nozzle.) That you pump by hand....

Set it on stream...

A lot of times it simple like a tensioner pully... but without pressure on it ..Generally it still wont squeak/squeal... Start the car up and squirt water on the bearings of the tensioner, ac unit pully, etc... when the noise disappears... you found where the squeal/squeak is coming from..

Be careful to not get any on the belt!

 

Does it sound like this?


http://m.youtube.com/watch?v=Ck8Hcw1...ure%3Dyoutu.be

 

Dbaldwin that is exactly the noise it's making

 

Ok so mine is the alternator bearings that are inside the alt itself, not the pulley. Its usually a sign of the alt starting to fail. Or it could be the power steering pump. Try changing out the ps fluid (good thing to do anyways) the only way to know for sure is to change out the alt. But if you put a screw driver to your ear and touch it to the alt if it sounds like thats what's making the noise then thats ads sure as you can get. My noise reduced when I replace the tensioner pulley and pcv valve. But still haven't replaced the alt.

 

PCV valve on the 3100 and 3400 is on the opposite side of the engine, no where near the pulleys (also it does not have the o-ring issue mentioned on the 3800, it plugs into the valve cover, held in with a grommet).

What concerns me is the statement about the crank pully seems to wobble. That pulley is the lowest pulley of all and should not wobble at all. That is cause for further investigation.

 

Now there's a noisy alternator...lol
I'd know that sound anywhere!

I also hear what sounds like a vacuum leak.

 

I'll go out here and do the ear test on the alt now. Hopefully it's just the tensioner pulley though, since that would be the most inexpensive resolution. I could get a ps pump at the junk yard for a good price, but an alt I would definitely buy new. I'll get back to you, thank you everyone for the tips.

If you guys want i'll go out here and take a video with my phone and put it up so you can see the crankshaft pulley in all it's wobbly wonder. Will be able to hear the noise it's making too. I'll post that soon as well, with the results of the "ear to screwdriver to alt" test.

 

David, i have feared that "woosh" sound to be a vacuum leak. But I haven't really had time to look into it. If im not getting a CEL. It can wait till spring hopefully.

Jason, wow.... I missed the LS part. Still yeah could be the alt.