[BonesNTX]

So on one of our 2005, 55K miles V8 Touaregs we have an occasional strange sound and bumping through the chasis however not felt in the steering wheel.

This sound is a bit of clumping from the passsenger side front axle area.
This occurs so far only after a speed bump and then a significant right turn. All of which is done at very low speed and after 1 or 2 right turns it quits only to be heard/felt after another speed bump and right turn.

Anyone know what could be causing this? Safe to drive?

Thanks

 

[Bagmaker]

Bones,


sounds like a wheel braking itself for either the ABS or EPS, if it is always from the same wheel this could indicate a wheel speed sensor on the way out.

Ensure all your tyres are the same diameter and pressures are within a few KPA (PSI) of each other. Cycle your gears a couple of times (engage low speed) and make it all work hard by turning on loose ground.

Then have someone observe the wheel from outside while you replicate the problem, they should see the wheel shud-shud-shuddering as it brakes by itself.

If the problems persists see your (brake) doctor.

bagger

 

[BonesNTX]

Bones,


sounds like a wheel braking itself for either the ABS or EPS, if it is always from the same wheel this could indicate a wheel speed sensor on the way out.

Ensure all your tyres are the same diameter and pressures are within a few KPA (PSI) of each other. Cycle your gears a couple of times (engage low speed) and make it all work hard by turning on loose ground.

Then have someone observe the wheel from outside while you replicate the problem, they should see the wheel shud-shud-shuddering as it brakes by itself.

If the problems persists see your (brake) doctor.

bagger

Thanks for the reply.

I just came from my Independent Shop and the owner and I were thinking maybe something related to brakes/Anti-Skid.
Nothing was revealed when on the lift, all looks fine and there was no noise when rotating the wheels with steering at lock positions.

Seems to me if it were brake related it would be felt through the steering wheel.

Of course we drove it around some, speed bumps and a jumped curb only to replicate this symptom once.

There is 2 pounds difference on the front tires. They are almost 10K miles old and recent balance/rotate.

I don't know what the ESP is for?

Why do you say "Brake Dr"? It is in need of rotors VERY soon.

Thanks

 

[Bagmaker]

Hi Bones,

tongue in cheek, "if in doubt, see you doctor" is the catchcry of pill sellers whose product seldom works.

My 04 has done the same thing a couple of times, to date the problem has gone away of its own accord.
This indicates (to me) a faulty sensor or other flexible, intermittant input into the computer.
I am unsure of all the inputs, perhaps a sensor relating to stability is also involved.

ie-
if the computer was faulty, the problem would show every time you did the same actions
if the brakes themselves were faulty, the braking would be otherwise affected at all times, mechanical things tend to do the same thing repeatedly as well.


the sensors and wiring for the sensors in the wheels relating to ABS and EPS are exposed to the elements, large amounts of dirt and constantly wearing components, they have a difficult job.

I would be checking there first.

But then, I am only guessing!


bagger

 

[BonesNTX]

"if the brakes themselves were faulty, the braking would be otherwise affected at all times, mechanical things tend to do the same thing repeatedly as well."

True....So it is most likely a sensor as opposed to mechanical.
Wait and see is the plan.

Thanks

 

[V10 FUN]

Bones,


sounds like a wheel braking itself for either the ABS or EPS, if it is always from the same wheel this could indicate a wheel speed sensor on the way out.

Ensure all your tyres are the same diameter and pressures are within a few KPA (PSI) of each other. Cycle your gears a couple of times (engage low speed) and make it all work hard by turning on loose ground.

Then have someone observe the wheel from outside while you replicate the problem, they should see the wheel shud-shud-shuddering as it brakes by itself.

If the problems persists see your (brake) doctor.

bagger

Have you inspected the upper and lower control arm bushings?

 

[BonesNTX]

Have you inspected the upper and lower control arm bushings?

How would I check the bushings? Warranted on a 57K Mile Vehicle?
Wouldn't a worn bushing most always react with the same symptom?

Thanks

 

[V10 FUN]

It is a visual inspection. Look for cracks in the rubber or signs that the material is pushed out of place.

My wife has an 06 Audi A8L with 63K that needs upper bushings. Oddly, they only clunk/pop when the car is cold. Upon inspection, the aft control arm bushing material appears to be failing.

 

[Mike's Panzer]

I had what I thought was driveline noise, turned out to be the Wrangler HP tires. They were very loud as they wore,at 3/32 they rmbled to a stop sign. They are now playground material.