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SpiderBy
11-16-2009, 04:21 PM
Folks,

Just finished with my first CV boot replacement exercise (front right), gave my car a test drive and damn!
Whenever I push brakes ABS is activated and I feel the brake pedal vibration.
And I am not braking hard!
There is also some buzz sound for a 3-5 seconds once I stop braking...

I did not remove the ABS sensor when I was pulling the axle from the hub.
And I cleaned the ABS sensor ring on the CV joint before I put it back to the hub.

Is it possible that I accidentally touched the sensor while I was struggling with mounting the upper arms to the knuckle?

Note, there is no ABS light or anything on the cluster.

What would you do now being in my place?
I am going to take off the wheel and remove and put back the ABS sensor. But I am not sure if it would help.

Dammit, it is really frustrating after getting job done understand that somehow I created a new problem...

TIA, guys.

stack
11-16-2009, 04:39 PM
i just had this problem.
just that my abs and brake lights were on.

when you put back the axel did you damage the teeth,
and look at the gap in between the wheel bearing and axel. and compare it to the other side.

my problem was the teeth were fcked up. and and the abs sensor did reach in all the way.
so check that.

also check turn tightly going very slow. see if you get clicking noise from your axel

AudiTechS4
11-16-2009, 04:46 PM
pull your speed sensor and make sure its clean

AudiTechS4
11-16-2009, 04:48 PM
only thing that doesn't make sense is that if you messed upo the sensor wheel some how i would think it would be activating all the time through abs even without using the brakes because it wouild be seeing different speeds at the 2 front axles. does your car have esp?

stack
11-16-2009, 05:00 PM
and did you plug out your abs sensor when replacing the axel???

SpiderBy
11-16-2009, 06:17 PM
Guys,

Just pulled out the ABS sensor, noticed some dirt on its end, cleaned it, pushed back, gave a test drive with active braking - everything is OK.

No ESP on my baby.

And no, I did not pull out the sensor when I was removing the axle... I actually thought I'd better not to touch it, but looks like it actually played against me.

Luckily, looks like I am good now. And with the new CV boot! [drive]

Thank you all, guys!

sr20det
11-16-2009, 07:42 PM
for future reference, I had the same problem and it was too large of a gap between the sensor and the abs ring. It was close enough to register speed and NOT throw an abs fault code (read with VAG-COM), I only figured out the problem with doing a few wheel sensor logs with the VAG-COM. Above 10mph my sensors read within 2-3kph of each other, but under 10kph, the 1 sensor with too large of a gap would be about 7kph off (intermittently) and activate the abs pump.

I am glad you figured out your problem, hope this helps someone out in the future.

AudiTechS4
11-16-2009, 07:49 PM
awe no rep :(

SpiderBy
11-17-2009, 04:50 AM
for future reference, I had the same problem and it was too large of a gap between the sensor and the abs ring. It was close enough to register speed and NOT throw an abs fault code (read with VAG-COM), I only figured out the problem with doing a few wheel sensor logs with the VAG-COM. Above 10mph my sensors read within 2-3kph of each other, but under 10kph, the 1 sensor with too large of a gap would be about 7kph off (intermittently) and activate the abs pump.

I am glad you figured out your problem, hope this helps someone out in the future.

Thanks a lot for this tip! I've got VAG-COM and going to examine the logs the way you suggested!