# Whirring noise when decelerating



## TTuned84 (Apr 25, 2011)

Hey guys, 

Just thought I'd run this by you before taking my car to the dealership and getting raped. So heres the deal: I have a whirring noise coming from what seems to be the dif. When i'm decelerating it starts to whir slightly and it seems to be speed sensitive. By the I mean is it gets louder as the speeds climb. But heres the thing, this only happens when I'm decelerating and off of the gas, if i press the gas pedal the noise goes away. 

Any thoughts?


----------



## 96AAAjetta (Jul 7, 2008)

Does clutch in/out make a difference? 

Could deff be a gear lash issue. Because when you are on the throttle, the engine is (obvioulsy) making power and loading the entire drivetrain. So the gears are in contact, a drive/driven situation, then when you let off the throttle the forward motion of the vehicle is now driving the gears. So if you have a shot bearing it could very well be allowing a pair of gears to be creating a noise on decel. I would say take it for a spin around the block from cold. Drive enough to the the gear oil in the trans and diff stirred up but not to get the oil too hot to touch, then crack open the oil fill in both diff and trans, stick a finger in (with the engine off) and see if it looks burnt, smells burnt, or has specs of metal. You should know if something is wrong. Gear oil has a natural stink to it but if your diff/trans has decided to frag itself it will have a special, other-wordly stank about it thats hard to describe.


----------



## corradojohnt (Sep 16, 2007)

It sounds like the Haldex Pump may be on the way out. In one of my last threads I posted a link to a pdf explaining how the Haldex system works. GL :beer:


----------



## TTuned84 (Apr 25, 2011)

Clutch in or out does not make a difference


----------



## TTuned84 (Apr 25, 2011)

96AAAjetta said:


> Does clutch in/out make a difference?
> 
> Could deff be a gear lash issue. Because when you are on the throttle, the engine is (obvioulsy) making power and loading the entire drivetrain. So the gears are in contact, a drive/driven situation, then when you let off the throttle the forward motion of the vehicle is now driving the gears. So if you have a shot bearing it could very well be allowing a pair of gears to be creating a noise on decel. I would say take it for a spin around the block from cold. Drive enough to the the gear oil in the trans and diff stirred up but not to get the oil too hot to touch, then crack open the oil fill in both diff and trans, stick a finger in (with the engine off) and see if it looks burnt, smells burnt, or has specs of metal. You should know if something is wrong. Gear oil has a natural stink to it but if your diff/trans has decided to frag itself it will have a special, other-wordly stank about it thats hard to describe.


 Also it doesnt matter what gear im in, the noise is just dependent on the actual speed of the car.


----------



## aTTenzione (Aug 18, 2009)

TTuned84 said:


> Also it doesnt matter what gear im in, the noise is just dependent on the actual speed of the car.


 wheel bearing


----------



## TTuned84 (Apr 25, 2011)

aTTenzione said:


> wheel bearing


 But when I press the gas pedal it goes away...so i doubt it'd be the wheel bearing


----------



## ILLA NOIZ (Jul 2, 2007)

I have a similar issues... I was thinking Power Steering. I hear it when I slow down as well.. especially when turning the wheel. Haven't had a minute to look into though. 

Poor car has been semi-neglected and in need of a good once over. I had a local VW mechanic that used to do work for me on the side... but has been MIA. I need to find another in the area.


----------



## ILLA NOIZ (Jul 2, 2007)

FYI - I ordered Power Steering Fluid (From Black Forest Industries - They are close and $20/shipped) One day delivery. 

I added enough to top off the fluid and drover her around the black. The noise was still there... but a little quieter. I checked the level again and it looked good. 

Took the TT out this morning early and drove a couple of miles, as I figured there may be air in the lines due to it being low. Sure enough... The whining is gone and the steering has improved. 

:thumbup:


----------



## TTuned84 (Apr 25, 2011)

ILLA NOIZ said:


> FYI - I ordered Power Steering Fluid (From Black Forest Industries - They are close and $20/shipped) One day delivery.
> 
> I added enough to top off the fluid and drover her around the black. The noise was still there... but a little quieter. I checked the level again and it looked good.
> 
> ...


But would you really hear it a lot when you are turning the wheel and not moving?


----------



## 96AAAjetta (Jul 7, 2008)

TTuned84 said:


> But would you really hear it a lot when you are turning the wheel and not moving?


That is when the power steering system has to work the hardest. So if it was making a noise, that would most likely be when you would hear it.


----------



## TTuned84 (Apr 25, 2011)

96AAAjetta said:


> That is when the power steering system has to work the hardest. So if it was making a noise, that would most likely be when you would hear it.


Right, so I don't have that issue. So is there any other thoughts on what the problem could be? Would the haldex fluid being low cause this?


----------



## quattrosNrabbits (Jun 23, 2007)

TTuned84 said:


> But when I press the gas pedal it goes away...so i doubt it'd be the wheel bearing


If it was a failing front wheel bearing, accelerating shifts the weight to the rear and could cause the front to stop complaining. Try doing tight circles in a parking lot if you hear the whir in a tight left, look at your RF bearing, in a tight right look at your LF bearing. You want to load up the bearings on one side and see if you hear one.


----------



## TTuned84 (Apr 25, 2011)

quattrosNrabbits said:


> If it was a failing front wheel bearing, accelerating shifts the weight to the rear and could cause the front to stop complaining. Try doing tight circles in a parking lot if you hear the whir in a tight left, look at your RF bearing, in a tight right look at your LF bearing. You want to load up the bearings on one side and see if you hear one.


I'll give that a try, thanks for the advice


----------



## Chuckmeister87 (Nov 10, 2009)

I've got the same issue. With the gas on, there is no noise. With it IN gear and foot off the gas, I hear a whirring noise that gets louder with speed. When I take it out of gear the sound stops. It doesn't make the sound when I do tight turns, but when I make a tight left it feels like the car is slipping trying to put the power down (even if I'm not going fast).

Also, when I reverse I'll sometimes hear a pop or loud click when I turn to the left. Where are the wheel bearings? I've put Raxels on my car and it didn't fix the sound (thought it was a bad CV):banghead:


----------



## Chuckmeister87 (Nov 10, 2009)

I need advice

*bump*


----------

