Hi all,

I was wondering if you can share your thoughts on diagnosing this problem. Its a tough one to describe to bear with me. I have a 2001 4DR LT 4 button 4x4.

I have a whine coming from somewhere in front and to the right of me when I'm driving.

• It might be happening all the time but its hard to tell (engine/road noise)
• It is not related to RPM
• It does seem related to speed, sort of - it gets loudest as I slow to a stop and continues for a few seconds after I am stopped (so not a wheel bearing)
• It then gets quiet - I'm pretty sure I can hear it at idle but it is hard to pinpoint the location
• Shifting into neutral doesn't change the sound - it doesn't seem to be transmission related
• Shifting into 4x4 doesn't change it.
• Turning AC/fans etc. on or off doesn't change it.
• I can't get it to happen just by revving the engine - I need to be moving for it to occur.

It sounds like it *could* be coming from inside the dash but its hard to tell, because I need to be moving and then slow down or stop to make it happen. It could just as easily be coming from the engine compartment (AC bearing or something?) or under the vehicle (I dunno, fuel pump?).

Anyways, any assistance in helping diagnose this is much appreciated!

 

well if you can hear it at idle that its an engine issue, i would pull the acc. belt off and try spinning all the acc. pulleys and see if one is rough spinning or has some play in it. if soo than you found your problem.

 

You say a "whine" a power steering pump whines when its low on fluid but you say its not RPM related and a pump would change with the rpms

Let me ask a question The "Whine" may be wrong word can you say the sound could be a squeal or a whistle

a squeal would could be a belt or a pulley but again that would change with the rpms

A whistle would be air or vacum related and would not change with rpms but could stop at high rpms and be loud at low and constant rpms

For example if your Idle Air Shutoff Solenoid gos bad they have been known to whistle (I havent seen this in a blazer but I have seen it on a venture and a carravan both minivans) This could be under the car towards the front
if you get a crack in a vacuum line it could whistle
It sounds to me you may have a vacuum problem

With out hearing it my self I would point you in that direction if you cant pin-point it get a chunk of hose and play doctor

 

Could be a whistle. Its actually really hard to describe, to be honest. Anyways, a vacuum line sounds promising, I will check that out. The only problem is that it isn't related to RPMs at all. I heard it when I am coming down from driving speed, and it is loudest as I am, say idling forward. So for example I would hear it when I am pulling into a parking space. It will stay loud when I am stopped - for a couple of seconds - then go down to a quiet background whine.

My ABS is also acting up (the hub bearings are going) so could it be related to the ABS system?

 

You said
"The only problem is that it isn't related to RPMs at all"
Just so you know I understand that
You also said
"I heard it when I am coming down from driving speed, and it is loudest as I am, say idling forward."

This is when your Vacuum is strongest at this point so I would make sence that it would be vacuum

When you hit you gas pedal your Vacuum drops because you engine uses it Most all this is why they use vacuum chambers to hold vacuum so (Example) your defrosters stay on and your vaccum controlled vents dont got to the floor

Abs problem no this isnt relater but the bad hub bearings I would bet that woudl add to it
Let me know how you make out
Happy Hunting :-)

 

how about this try to get a video of the sound

IT will make it way easier for us to try to help you diagnose the problem

 

I had something similar happen with the hose on my PCV valve. The sound was somewhere between a whine and a whistle, related to RPM, but not directly.

I had replaced the hose with some I had around, and it took it a while to go bad. It basically softened up and would compress from the vacuum. And of course I didn't suspect it, having replaced it already.

 

Regarding the ABS : have you cleaned the wheel sensors? They're magnetic, and like to hold onto stuff. I hit them good with compressed air when changing pads.