Mystery Belt noise......

So a few months ago the VX started to make a belt slipping type noise upon start up but would go away. Then it started to happen when I would turn the wheel. Then it would only make the noise when the A/C was on. So the noise got so annoying that I would drive with the windows down, but got annoying so I decided to try and fix the problem. Here is the order in which I tried to fix this mystery noise:

-power steering pump (helped noise a little temporarily)
-tensioner pulley (helped temporarily)
-A/C compressor (much quieter overall but mystery noise still came back)
-alternator (much quieter overall but mystery noise still with A/C on and turning)
-power steering pump (tried this again, maybe just got a bad pump, nope)
-New Belt (uh no luck)
-tensioner pulley (tried again this time with higher quality metal part, nope)
-Idler Pulley (installed by shop and they said it did not fix the issue, update 9-13-11)

Did you replace the serpentine belt? I had a squeaky engine noise that I thought was the idler pulley but I bought a new serpentine belt first and the noise went away. The old belt was just stretched enough to slip but not the typical squeal you hear from old cars starting up, this was a more constant annoying noise.

Oh yeah sorry forgot to mention that in there. Yes belt was replaced twice as well :-)

Well at least you've got all new pulley's and accessory parts/pumps on the engine now!

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Originally Posted by LittleBeast

Oh yeah sorry forgot to mention that in there. Yes belt was replaced twice as well :-)

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Yeah I figured you replaced it already. Hopefully its the idler pulley, having a problem you can't figure out is a major pita.

Haha, so shop called today, and the idler pulley did not fix it like I was suspecting.....

So while I am gone to France for my last meet of the season this weekend they are going to try and find the real issue, haha :-) I will be back next monday and hopefully I will have something positive to report.

Timing belt idler pulley??? Belt could still be in it correct notches, but slipping over a seized or lazy idler pulley.

Other option is the bonnet support rubbers. Does it still make the sound with the bonnet up?? (Youawl might call it a hood.)

PK

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Originally Posted by PK

Timing belt idler pulley??? Belt could still be in it correct notches, but slipping over a seized or lazy idler pulley.

Other option is the bonnet support rubbers. Does it still make the sound with the bonnet up?? (Youawl might call it a hood.)

PK

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Haha, yes it makes the whine noise when you get on the gas with the a/c on, standing still or driving, and when turning the wheel with the A/C on, and also every time upon startup regardless of what is on or off.

Hey, I've got that noise too! Strange thing is recently the noise has gotten quieter. I surmise that it is being caused by one of the belt idler pulleys on my timing belt. Coming up on 120,000 since my last timing belt change, so I figure it's about time to do the deed.

Had something a bit similar... It was the power steering pump! Drained the the fluid and replaced it with new and some lucas power steering additive....... noise gone!

I've gad similar problems with other vehicles and have always been able to isolate belt issues with a shot of belt dressing on the drive-side of the belt with the engine running. If you don't have belt dressing, WD-40 will work too as it conditions rubber and prevents it from drying out. Give it a "shot" and see if that answers any questions! Best of luck in your gremlin chase.

I also tried the belt dressing. This is something a bit different :-)

So I just got back in from my meet in France so the shop had my VX for a while now tracking down this noise and they said they definitely have it pin pointed.

So it seems the Crankshaft pulley or the Harmonic Balancer has gone bad. They said they marked the old worn out rubber on the pulley and when it would stick is when the noise would occur. Sounds good to me.

Thank goodness for RockAuto.com !!!!! Prices as listed:

2001 Isuzu VX Crankshaft Pulley / Harmonic Balancer:
-Isuzu Parts.com AND Merlin @ St Charles = $223.52
-Amazon.com = $230.39
-RockAuto.com = $125.79

So did changing the Crankshaft Pulley / Harmonic Balance work? :)

Head Mechanic's wife was in the hospital Friday, but they said it was ready, so I will pick the LittleBeast up tomorrow and report on the sound after. Sounds like they are happy with the results though.

VX sounds like new again!!!!!

The source of the belt slipping noise was in fact the Crankshaft Pulley / Harmonic Balancer. $130 part from RockAuto and no noise upon startup or when I turn the A/C or when I turn the steering wheel at slow speeds.

So if you are experiencing any type of noise upon startup or when ac comes on or when turning do not rule out the Crankshaft Pulley / Harmonic Balancer.

I am very happy to have this noise Fixed finally.

Glad to hear it was successful.