Weird noise at idle

[cwelk87gn]

I have been chasing down a strange noise and need some advice/suggestions. Idling in park with the A/C on the car makes a noise that can best be described as a heat shield rattling and a whine. I have replaced the idler pulley, water pump and listened to the alternator and compressor with the old screwdriver to your ear trick and can't find it. With the A/C off, it still makes a rattling noise but its hard to locate. I have watched the crank pulley and its as solid as a rock. All I can say is that it seems like its coming from the upper front part of the engine.

 

[buickboy]

Pretty common noise is the crank sensor rubbing the balancer interupter ring. If that is what it is, you wil get stranded when the sensor breaks.
Mitch

 

[Dan Buick Man]

Check your intercooler conections. I had a knocking noise that was simply a loose bolt on the left side of the intercooler.

 

[cwelk87gn]

Originally posted by buickboy
Pretty common noise is the crank sensor rubbing the balancer interupter ring. If that is what it is, you wil get stranded when the sensor breaks.
Mitch

How is this problem fixed? I don't want to take a walk on the highway...

 

[pacecarta]

im still new to turbo regals but in trying to track down my noise source that was most noticable at low idle it was suggested to check the rear of the a/c compressor bracket for a mtg bolt that can come loose and rattle ,

mine turned out to be none of the usual suspects ,
i had a new dayco belt so I thought that I had eliminated that as a source
turns out the new stock lenght belt was causing the tensioner to be nearly at its limit and resulted in a bouncing tensioner (to minute too visually see) and at low idle it would sound like a knock when the tensioner bottomed out
the fix was simple , a new shorter goodyear belt ,

see if the noise is present without the belt ,hopefully the noise will dissapear and narrow down your search to the accessories and their mounting brackets, if you still hear it with belt off then maybe it is the crank sensor clearance as suggested above

 

[SFITurbo]

Had the same noise on mine. Ended up being a/c clutch bearing on the way out. Couldn't locate it for sure until it got worse. Drove me nuts cause it started after I rebuilt the motor and thought I screwed something up big time.