ABS engages everytime I brake wtf?

**pearlescent** · 01-31-2010 04:50 PM

So I changed out my rear wheel bearings, rotors and pads. Everything went smoothly. Now almost every time I hit the brakes my ABS engages.

I can feel the pulsating in the pedal and can hear the typical noise from the master cylinder. ABS light is not on. I did not bleed the brakes when I retracted the caliper piston, I've heard that this can cause problems.... HELP!

**Vrdady** · 01-31-2010 04:52 PM

Originally Posted by pearlescent

So I changed out my rear wheel bearings, rotors and pads. Everything went smoothly. Now almost every time I hit the brakes my ABS engages.

I can feel the pulsating in the pedal and can hear the typical noise from the master cylinder. ABS light is not on. I did not bleed the brakes when I retracted the caliper piston, I've heard that this can cause problems.... HELP!

typical of bad ABS sensor. but since you did your brakes I'd suggest going back and making sure you didn't break or unplug something.

**Dre_audi** · 01-31-2010 04:59 PM

My advice is to go back and check if you left anything unplugged or damaged anything this happened to me and it turned out my mechanic did not put the sensor back in properly good luck

**Crispy222** · 02-01-2010 12:39 AM

defiantly a sensor issue.

**dangerous_dave** · 02-01-2010 02:24 AM

If the rear sensors are anything like the front you probably just moved one of the sensors slightly out of the hole when you removed and installed your rear axels. Try pushing them back in before you try diagnosing a faulty sensor. This happens to me alot when I do front cvjoints or replace axles Usually pushing the sensor back in fixes it.

**pearlescent** · 02-01-2010 09:26 AM

okay, thanks guys I'm gonna pull them out and try to make sure they are fitted properly.

Is it safe to say that if my ABS light isn't on the sensors are still okay?

**walky_talky20** · 02-01-2010 09:43 AM

I've heard cleaning the end of the sensor off can help sometimes as well. If it gets some rust or metal chips stuck to it, it can affect the reading.

This is why it is sometimes advised not to remove the wheel speed sensor when replacing the rear wheel bearing. Just unplug it under the seat, fish the wire through the grommet, and leave it attached to the hub during the procedure. That's how I did it, I didn't want to risk breaking it as they often get seized in there pretty good.

**pearlescent** · 02-01-2010 09:28 PM

Originally Posted by walky_talky20

This is why it is sometimes advised not to remove the wheel speed sensor when replacing the rear wheel bearing. Just unplug it under the seat, fish the wire through the grommet, and leave it attached to the hub during the procedure. That's how I did it, I didn't want to risk breaking it as they often get seized in there pretty good.

Yup, I found this out from my Bentley manual today... wish i would have known before I started twisting the sensor out. I found out that i cracked the magnet in the sensor, not tripping the ABS light but causing a bad reading. For now, no ABS for me. I replaced my wheel bearings and screw up my ABS, seems so typical of B5 maintenance haha

**chris164935** · 05-20-2010 03:33 PM

Originally Posted by pearlescent

Yup, I found this out from my Bentley manual today... wish i would have known before I started twisting the sensor out. I found out that i cracked the magnet in the sensor, not tripping the ABS light but causing a bad reading. For now, no ABS for me. I replaced my wheel bearings and screw up my ABS, seems so typical of B5 maintenance haha

Was the cracked magnet in the sensor visibly obvious?

**pearlescent** · 05-20-2010 04:02 PM

Originally Posted by chris164935

Was the cracked magnet in the sensor visibly obvious?

Yup, the casing and the magnet itself were completely severed haha

**sethmedeiros** · 02-23-2012 03:56 PM

im having the same issue, im hoping it will just be dirty sensors or metal stuck to the end of it, from when i had to bangout the old one. its super dngerous to drive now i come to stop signs andat 5 mph cant stop i have to use the ebrake to coax myself to a stop, can i just unplug the abs sensor to stop this, id rather have no abs then NO Brakes, thanks.

**mysman** · 02-23-2012 06:56 PM

Pull the ABS fuse, I believe.

**FNK** · 02-23-2012 07:50 PM

This also happened to me, it wasn't the sensor, it's the ABS ring who splitted in two. Welding it didn't worked.
You can use VAG to identify this problem under ''Abs ... out of run somthing''... well this was of no help

**B5Bandit$** · 02-24-2012 09:22 AM

This also happens to me sometimes, but it seems it only happens on inclines or when breaking in dips in the road.

**$teady$upreme** · 04-10-2012 11:06 PM

Originally Posted by B5Bandit$

This also happens to me sometimes, but it seems it only happens on inclines or when breaking in dips in the road.

Did you find out what your problem is?

**rssparks** · 04-17-2012 11:05 AM

i have the same issue only the ABS only engages from about 20mph down to the 13mph range. It pulsates while slowing down, just at those speeds though. Once above or below that range the brakes and ABS work fine. I had brakes and both front axels replaced in the last 3 weeks. should I just check all the sensors before ordering new ones??

**wildbill** · 04-17-2012 01:56 PM

for those who have issues. a fix it...or b ....unplug the harness. i ran my car that way for two years never had an issue. not ideal, but it helps. my car would lock the driver rear while going down the highway. i will say this...never buy a car from certain foreigners....f'n liars. and its not the first time its happened.