On-and off grinding on hard left and traction control light...

This is a really strange issue and I bet one you really smart people has seen it before.

The issue has happened three times in the last few days, and has only happened on one specific turn on one specific road. Traveling down a slight hill (so very little engine load on drive shaft, CV joint, etc) at 40-45 MPH or more, the road makes a pretty sharp left. Going around the turn there is an intermittent burst of what I would describe as a grinding noise from the right front. Three burst of grinding lasting between 1 and 2 seconds total. I can also feel it in the steering wheel.

What is interesting is that when this is happening, the traction control light flashes a few times.

After passing through the curve the noise goes away and the car seems normal.

I have tried to repeat it by driving hard into other curves, but nothing.

I pulled the RS wheel off. I have a torn outer tie rod boot but the tie rod end still seems tight. I am going to replace the tie rod end, but is there any chance that the tie rod end can be causing this? I'm thinking maybe the sound but probably not the traction control light. I thought about a wheel bearing, but I've had wheel bearings go before and the sound did not pulse like this.

I am stumped.

I doubt it's the tie rod but with a torn boot it does need replacement sooner or later. That grinding pulse is probably your abs and the traction control light will flash when a wheel slips. If you have a VCDS you could check for stored codes, a generic scanner will not read the abs module.

Tdijarhead said:

I doubt it's the tie rod but with a torn boot it does need replacement sooner or later. That grinding pulse is probably your abs and the traction control light will flash when a wheel slips. If you have a VCDS you could check for stored codes, a generic scanner will not read the abs module.

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The sound is not an ABS pulsing sound. What I can't figure out is why would there be a wheel slip on a dry road (accompanied by the off and on "grinding" sound).

I have VCDS so that's a good idea to check for codes. No CEL though, so maybe no codes.

It may not actually be wheel slip, the computer might just be reading it as slip. Is there any possibility that the tone ring the abs sensor uses to determine wheel speed is dirty or bent? Though if that were true it seems like there would be more than one very specific instance on this happening. Do the VCDS and see if it tells you anything.

Look first for a CV or bearing. For whatever reason my experience has shown that odds favor the right front wheel. Usually the bearing.

Place the car safely on stands or a lift. Do the following:

Grab top and bottom of the front tires and attempt to chuck up and down. Turn the tires 90 degrees and do the same. No chuck allowed.

Place your hands at 90 and 180 degrees and attempt to chuck tires right and left. Observe your suspension components while in the process. You should be able to see a failing tie rod end even if you can't feel it. Usually the socket end will move slightly up and down on the ball.

Cramp either right or left and roll the tires one at a time. You should detect nothing but a smooth rotation. Not even a slight roughness or a "bump" allowed. Cramp in the opposite direction and do the same. If in question remove the tires and do the same as the weight and inertia of the tire and wheel assembly can mask roughness and slight grinding noises.

Straighten your steering, then check both half shafts. You'll be looking for failed boots and you'll attempt to chuck each shaft up and down as you rotate through a full 360 degrees. You'll also be looking for any slack between the inner (transmission side) and outer (wheel side) of each shaft as you roll your tire back and forth. Again, none allowed.

As I shared above, my experience has been that you'll find the right front bearing to be failing. Obviously I'm not there and I could be wrong. In any case you'll have done a pretty thorough check of your front steering and suspension which should be a general maintenance item anyway.

richmondvatdi said:

The sound is not an ABS pulsing sound. What I can't figure out is why would there be a wheel slip on a dry road (accompanied by the off and on "grinding" sound).

I have VCDS so that's a good idea to check for codes. No CEL though, so maybe no codes.

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Do you have ESP?

It IS the ESP. For some reason the controller are being told (correctly or not) that the car is not moving in the direction the steering wheel is pointing. The wheel has an angle sensor that should be within a few degrees of a reference when driving straight ahead. The wheel rotation speeds are compared to estimate a turn radius. When the values of the turn radius and the angle of the steering wheel don't match, and the car's speed is above some threshold, the ESP activates.

Confirm the tires are at the correct pressure and are the same size and similar wear condition.
Confirm the angle sensor is set to the correct reference.
Confirm the wheel alignment has the steering wheel straight ahead when driving straight ahead.

Sounds like experience? Yep.

I ended up changing both of my sensors under the steering wheel. Yours is a combination sensor.

It would not throw a DTC because it was "working" but not when they're supposed to.

UPDATE: Found some hub damage. Can this be the cause?

Lug_Nut said:

It IS the ESP. For some reason the controller are being told (correctly or not) that the car is not moving in the direction the steering wheel is pointing. The wheel has an angle sensor that should be within a few degrees of a reference when driving straight ahead. The wheel rotation speeds are compared to estimate a turn radius. When the values of the turn radius and the angle of the steering wheel don't match, and the car's speed is above some threshold, the ESP activates.
Confirm the tires are at the correct pressure and are the same size and similar wear condition.
Confirm the angle sensor is set to the correct reference.
Confirm the wheel alignment has the steering wheel straight ahead when driving straight ahead.
Sounds like experience? Yep.

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OK, I've had a few major life issues to deal with over the last several weeks and now I am back to this problem. To those of you who said it was the ABS actuating, you are correct. Pulled both wheels cleaned up the ABS sensors and reinstalled them. Then checked the ABS rings on the hub. Right looked normal but left had a spot like this. It looks like it took a pretty hard whack and is noticeably indented. What are the chances that this is causing the ESP to activate around high speed curves? Should I just go ahead and replace the hub or is there other diagnostic work I can do to definitively identify the culprit? (I have VCDS but don't know exactly how to use it to identify an ABS malfunction. I verified that there are no stored codes.)

Also, how I determine that the angle sensor is set to the correct reference? I just had an alignment done so I am confident the wheels are pointing straight ahead.

The steering angle sensor is under brakes, but I forget which group. The Ross tech site has that info if I remember correctly. With your wheels pointed straight ahead the value should be 0 or close to that. There is a few degrees of tolerance.
Judging from the picture, I think you've found your culprit. Good catch.

As to diagnosing if you get a helper to drive and recreate the turn that the slip seems to be happening. Plug your VCDS in and watch. Under brakes there is a group that displays all four speed sensors at the same time with wheel speed. As you recreate the turn the speed sensor for that wheel (pictured) should be the one that is off significantly, when the dash light comes on.

Tdijarhead said:

The steering angle sensor is under brakes, but I forget which group. The Ross tech site has that info if I remember correctly. With your wheels pointed straight ahead the value should be 0 or close to that. There is a few degrees of tolerance.
Judging from the picture, I think you've found your culprit. Good catch.

As to diagnosing if you get a helper to drive and recreate the turn that the slip seems to be happening. Plug your VCDS in and watch. Under brakes there is a group that displays all four speed sensors at the same time with wheel speed. As you recreate the turn the speed sensor for that wheel (pictured) should be the one that is off significantly, when the dash light comes on.

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I found that display of wheel speeds in the ABS module in VCDS. I think it is either group 1 or 2. My question is, is there a way to record those values as they change through the curve (either by logging or graphing) or do my co-pilot's eyes have to be quick enough to see the numbers change in real time as the ABS pulses?

I'm not sure about graphing those numbers. I really never looked for a graphing capability for the speed sensors. I think you'll notice the difference though, especially if you pay attention to the suspected wheel.

That chip in the tone ring should make no difference. you can use VCDS to see the value being given for that wheel. I'd get a helper to drive the car.

This is my guess Yaw rate sensor

https://www.google.com/webhp?source...w+rate+sensor&tbm=shop&spd=597119047141683251

http://www.partsbase.org/vw/jetta-j...or-acceleration-and-yaw-rate/#p-vw-1j0907655a

Why not just bend that sucker back in to position (making sure you're not bending it too far out towards the sensor) and then seeing if that resolves the issue? I think that that ring needs attention any way you look at it (and it appears that it's been like this for a while.

It's not bent, it's chipped. If that chip affected the ABS, it would do it all the time. The fact that it happens when you create a LATERAL force by turning the car points to the YAW rate sensor. if the steering angle sensor is bad, it'll show up in VCDS.

At least start with spraying the connector to it with Deoxit. but you will need to end up replacing the sensor. I struggled with mine for a YEAR before I replaced it. Would only happen when it got cold outside. Wouldn't do it in the summer.

tongsli said:

It's not bent, it's chipped. If that chip affected the ABS, it would do it all the time. The fact that it happens when you create a LATERAL force by turning the car points to the YAW rate sensor. if the steering angle sensor is bad, it'll show up in VCDS.
At least start with spraying the connector to it with Deoxit. but you will need to end up replacing the sensor. I struggled with mine for a YEAR before I replaced it. Would only happen when it got cold outside. Wouldn't do it in the summer.

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Thanks for the links to the yaw rate sensor. There are a bunch of used ones for sale around $50 but a new one from VW is over $600. Is the steering angle sensor a different part or is it the same thing as the yaw rate sensor?

richmondvatdi said:

Thanks for the links to the yaw rate sensor. There are a bunch of used ones for sale around $50 but a new one from VW is over $600. Is the steering angle sensor a different part or is it the same thing as the yaw rate sensor?

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Steering angle sensor is at the steering wheel, so different sensor

richmondvatdi said:

Then checked the ABS rings on the hub. Right looked normal but left had a spot like this.

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tongsli said:

That chip in the tone ring should make no difference.http://www.partsbase.org/vw/jetta-jem-us-2003-92700-control-unit-for-abs-speed-sensor-electronic-stabilisation-program-esp-combi-sensor-for-acceleration-and-yaw-rate/#p-vw-1j0907655a

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The ABS is actually looking at the 'holes', not the edges of the ring. As long as the metal between the holes passes the sensor as a rate within some percentage of the other three wheels rate, the ABS will be happy.
And because the sensor changes angle with the wheel the sensor to ring gap never changes. Turning would make no difference.

If the steering wheel angle sensor display is at zero (or within the accepted deviation from zero) when the steering wheel is set to whatever produces straight ahead travel, the steering angle sensor is not suspect.

How simple can a fix be? My intermittant ESP activation on down-hill left turns was solved by air pressure in the tires.

I would try bending it back like UhOh suggested, before I spent money on a new hub. Like I suggested get a helper to drive, plug in the VCDS, call up the measuring blocks for the speed sensors and take it for a drive and reproduce the circumstances that you have described. I think you'll be able to determine soon enough if that wheel is the problem, or you have something else going on.

Tdijarhead said:

I would try bending it back like UhOh suggested, before I spent money on a new hub. Like I suggested get a helper to drive, plug in the VCDS, call up the measuring blocks for the speed sensors and take it for a drive and reproduce the circumstances that you have described. I think you'll be able to determine soon enough if that wheel is the problem, or you have something else going on.

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It's not bent, so don't bend anything

tongsli said:

It's not bent, so don't bend anything

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I know you said chip, but to me it would appear to be bent and even broken with the broken part pushed in distorting the lower part of the hole. It looks like it could be put back into place, maybe I'm wrong after all I'm just looking at a picture and don't have the tone ring in front of me.

After he hooks up VCDS, and figures out if that wheel or another is the problem, or if it is something entirely different. If it proves to be that wheel and there seem to be no other options of what the problem could be, I would try to fix that break/chip/bend or whatever it is before I replaced the entire hub assembly.

I always like to do the simple first, and work up from there. I'll be interested to see if that little spot is causing his problem or if it's something else. Hopefully he keeps us updated with the solution.

Tdijarhead said:

I know you said chip, but to me it would appear to be bent and even broken with the broken part pushed in distorting the lower part of the hole. It looks like it could be put back into place, maybe I'm wrong after all I'm just looking at a picture and don't have the tone ring in front of me.
After he hooks up VCDS, and figures out if that wheel or another is the problem, or if it is something entirely different. If it proves to be that wheel and there seem to be no other options of what the problem could be, I would try to fix that break/chip/bend or whatever it is before I replaced the entire hub assembly.
I always like to do the simple first, and work up from there. I'll be interested to see if that little spot is causing his problem or if it's something else. Hopefully he keeps us updated with the solution.

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The early tone rings are not removable. Some of the recent aftermarket versions I've seen can be removed.

If his is the non-removable type he will have no choice but to replace the hub.

REMOVEABLE TONE RING



FIXED TONE RING
I think the shadow/lighting is distorting the situation in the photo

I was able to test the steering angle sensor and the yaw rate sensor. Both are well within the specs listed on the ross-tech website. I tried several times to check the measuring blocks while driving but VCDS keeps dropping the connection to the car after a short time so I haven't been able to check the wheel speed sensors when the ESP activates.

I am going to check the air pressure just in case, but I am tempted to change the hub/tome ring/bearing and see if it fixes it. I already have a spare wheel bearing on my shelf and the hub is only $50.

richmondvatdi said:

I was able to test the steering angle sensor and the yaw rate sensor. Both are well within the specs listed on the ross-tech website. I tried several times to check the measuring blocks while driving but VCDS keeps dropping the connection to the car after a short time so I haven't been able to check the wheel speed sensors when the ESP activates.

I am going to check the air pressure just in case, but I am tempted to change the hub/tome ring/bearing and see if it fixes it. I already have a spare wheel bearing on my shelf and the hub is only $50.

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Over a period of a year, my Yaw rate sensor NEVER threw a DTC. Only once did the second sensor throw a code giving me a hint to change it. after reading, and reading and reading and searching on the internet I took a leap of faith and changed both of my sensors related to ESP. I have two, you have only one under the steering wheel.

I too always blamed the ABS sensors and wires, in fact I still have the replacements which I never installed because I went with changing the sensors.

Changing that tone ring will not fix your problem, but I hope I'm wrong.

From ebay:
Yaw rate sensor repair
http://www.ebay.com/itm/Repair-of-y...ash=item3aa1d734c1:g:9yoAAOSwEeFVOM0L&vxp=mtr

www.modulemaster.com does Yaw rate sensor fix and is in the USA

In the mean time, some reading for you:

http://www.benzworld.org/forums/w163-m-class/1336514-yaw-rate-sensor-esp-bas-light.html

http://newbeetle.org/forums/questio...beetle/49890-yaw-rate-sensor-part-number.html

http://www.volkswagenforum.co.uk/showthread.php?t=15675

http://www.audiworld.com/forums/a6-s6-c5-platform-discussion-7/esp-problems-02-2-7t-a6-2746849/

http://www.vwaudiforum.co.uk/forum/showthread.php/114393-YAW-RATE-SENSOR-DEFECT-02-1-8T-Passat

http://www.passatworld.com/forums/volkswagen-passat-b5-discussion/373809-yaw-rate-problems.html

http://uk-mkivs.net/topic/19388-yaw-sensor-woes-now-with-pics/

Some of the folks thew codes, but others did not. I think if I would have left it alone, the ABS light would have happened more and more often eventually throwing a DTC that I could scan. I believe it's a degenerative-type fault.

Great information tongsli. I've got some reading to do and with the workload at my day job it may be a while before I read enough to figure out what is going on.

From the skimming of the threads that I have done so far, it seems like there is no definitive way to know the yaw rate sensor is dying until it begins throwing codes. I have zero stored codes at this point.

richmondvatdi said:

Great information tongsli. I've got some reading to do and with the workload at my day job it may be a while before I read enough to figure out what is going on.

From the skimming of the threads that I have done so far, it seems like there is no definitive way to know the yaw rate sensor is dying until it begins throwing codes. I have zero stored codes at this point.

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unfortunately, I believe that is the case. You can do what I did and just dis-able the ESP when it malfunctions until you decide to try a new sensor.

Be careful not to spend too much money replacing otherwise good parts. I wish you luck and hope you get things sorted.

I know it can be frustrating as I've been through it myself.

How can I tell if mine is Mark 20 or Mark 60?

When you plug your VCDS in and go to the brake section. As it connects to the controller it reads which system you have and displays it. You probably have the 60 but VCDS is the final authority. Have you gotten to the bottom of this issue yet?

Tdijarhead said:

When you plug your VCDS in and go to the brake section. As it connects to the controller it reads which system you have and displays it. You probably have the 60 but VCDS is the final authority. Have you gotten to the bottom of this issue yet?

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No I haven't. I used VCDS to check the steering angle sensor and lateral acceleration sensor and they (at least according to VCDS) are reading correctly. It does not seem to be getting worse. Just trying to figure it out.

richmondvatdi said:

How can I tell if mine is Mark 20 or Mark 60?

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You can tell by looking athe ABS pump. There are 6 lines going to the big block of aluminum - 2 from the master, 4 going to the wheels.

On a Mk20, all 6 are are the side of the block.
On a Mk60, two are on top, 4 on the side.

The change was made in early 2001 (my Jan 01 Golf has a Mk60) so your 2003 surely has a Mk60.

Mk60 pump, the red plugs are where the lines go - 2 on top, 4 on the side: