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b00st
03-19-2006, 04:31 PM
my abs light came on...vag said speed sensor...anybody got any part #'s & prices...front right if that helps.

just had my suspension put on finally. H&R sports and Bilstein grooved shocks. love the setup....ultra happy with the purchase.

front grooves are set on the second from the bottom. rears are on the bottom perch. the car is not raked....very even. i think the fronts were originally a 3 finger gap and the rears were a 4...now both are a 1 finger gap.

next up...install rieger body kit, its time to get that out of the garage.

i will post pics tomorrow of the suspension. i am ULTRA happy with the purchase. definitely completes the look. looks 10x better...especially now that my 18s are back on. and we are supposed to get snow on tuesday here in chicago.[:(]

aberke
03-19-2006, 04:34 PM
never really heard anyone use ultra as a common adjective

drlandry00
03-19-2006, 04:50 PM
seems like whenever people do suspension installs it fucks up the speed sensors... i know you have to replace the axel along with the speed sensor. i guess the sensor is attached to it.. dont know where to get it... best of luck.

SeKKeY
03-19-2006, 04:53 PM
Originally posted by aberke
never really heard anyone use ultra as a common adjective

yeah must be a chicago thing. lol jk
ULTRA cool man

AudiA4_20T
03-19-2006, 06:44 PM
Originally posted by aberke
never really heard anyone use ultra as a common adjective

true, but ure not helping the guy at all and that had no relavence to anything.... [:)]

b00st
03-19-2006, 07:10 PM
Originally posted by aberke
never really heard anyone use ultra as a common adjective

thats for the grammar tip....so now back to topic.

speed sensor and why its screwed.

not sure why ride height would affect the speed sensor...but buying a new axle is not an option. is that really necessary? can't just swap out sensors?

somebody else with suspension must have come across this issue...and what was the fix?

drlandry00
03-19-2006, 07:14 PM
i did the same thing, that is why i said the suspension install fucks the sensor, it happens when you really twerk the wheel setup.. i know of 3 cases this has happened when changing susp.

the sensor might be kinked, bent, dented, you can take all the abs sensors out and check the ring on the axel.. i just adj mine with a screw driver so the sensor could read the correct spaces on the sensor ring..

i think that is what you are talking about..

or is it the actual sensor, like the cyclinder thing that sticks into the wheel bearing unit?

TheObiJuan
03-19-2006, 07:15 PM
I had to mess with the speed sensors, they are located right outside of the axels, where they go into the tranny.
They are a pain to work on.
Have you tried calling the dealership for prices or part numbers?

b00st
03-19-2006, 08:08 PM
well i just had my suspension installed and brakes bled.

i'm thinking its just the sensor....so really this happened during the suspension install? should i be calling the place that installed them? i know that when my car went in...no sensor...when my car came out...i now have the ABS sensor light on. so something happened during the install is my guess.

i was going to try and fix the situation....don't have a clue how as i didn't do the install or forsee this issue.

b00st
03-19-2006, 08:14 PM
Originally posted by drlandry00
i did the same thing, that is why i said the suspension install fucks the sensor, it happens when you really twerk the wheel setup.. i know of 3 cases this has happened when changing susp.

the sensor might be kinked, bent, dented, you can take all the abs sensors out and check the ring on the axel.. i just adj mine with a screw driver so the sensor could read the correct spaces on the sensor ring..

i think that is what you are talking about..

or is it the actual sensor, like the cyclinder thing that sticks into the wheel bearing unit?

i'm guessing/hoping the sensor is kinked, bent, etc...and that i can be adjusted back to its setting. i dunno if i can fix the situation or not.

RedRocket
03-19-2006, 08:18 PM
No need to buy a new axle. At the worst, you will have to replace the CV joint. That is, if the WSS got damaged, perhaps it just happened that the ABS system fucked itself by coincidence just now. Not likely at all, but I'm just letting you know that neither I, nor anyone on this forum can tell you exactly what to do.

However, I am 98.63% sure it's the WSS on the CV joint.

You don't have to replace it as long as you didn't really mash the teeth on it.

You have to inspect all the teeth on it to make sure none got wacked. I had one CV joint with a tooth missing, completely off. I had to replace that one. The other I dinged myself. I then took a metal file (nothing special) and filed the fattened part off and the gap between the teeth was good again. Problem fixed.

RedRocket
03-19-2006, 08:21 PM
And another one of my historical posts [:)]

Changing wheel bearings involves work around the abs sensor system. If the mechanic is not careful, certain things can go wrong and you will have an irregular and spontainous triggering of the ABS system.

If you don't know lots about how it works in our cars, briefly there is a ring of teeth that goes around the CV joint inside the hub (Wheel Speed Sensor). The ABS sensor looks like a metal rod, probably megnetic or something. It comes in from the outside and fits through the hub, reading the teeth. As your wheel spins, it monitors the speed at which these litte teeth are going by.

What your experiencing IS the ABS kicking in when it shouldn't. There are three possible causes:

1. The sencor wires have been cut. NOT likely, because then the effects would be constant.

2. The actual sencors are damaged somehow. Maybe, but you'd have to be a very amateur mechanic to make this mistake in my opinion.

3. Teeth on the Wheel Speed sensor have been disturbed. I AM 99% certian this is your issue. More than likely one of the teeth on the wheel speed sencor(s) have accidently banged off some other parts and it's giving off a funny reading to the ABS.

If you discover that this is the case, and the Wheel Speed sensors have been infact damaged, your mechanic should be 100% liable since that part has nothing to do with a wheel bearing. Replacement would be best otherwise, you may be able to file and reshape the one or two teeth that have lost their clean square shape.

I know this because that's what happened when I changed out my own wheel bearing. I filed out the imperfection in this case and everything was fine. Also when I bought my A4, one of the teeth whs broken off somehow, replacement was necessary in that case.

b00st
03-19-2006, 08:22 PM
well i didn't do the install so i'm not sure what happened, i had the local tuner do it.

should i take this up with my tuner? since i didn't do this myself...i have no idea what any thing looks like under there...could be crushed. could be whatever. i just wasn't sure where to start. or how much i was looking at to get it fixed.

b00st
03-19-2006, 08:27 PM
Originally posted by RedRocket
And another one of my historical posts [:)]

Changing wheel bearings involves work around the abs sensor system. If the mechanic is not careful, certain things can go wrong and you will have an irregular and spontainous triggering of the ABS system.

If you don't know lots about how it works in our cars, briefly there is a ring of teeth that goes around the CV joint inside the hub (Wheel Speed Sensor). The ABS sensor looks like a metal rod, probably megnetic or something. It comes in from the outside and fits through the hub, reading the teeth. As your wheel spins, it monitors the speed at which these litte teeth are going by.

What your experiencing IS the ABS kicking in when it shouldn't. There are three possible causes:

1. The sencor wires have been cut. NOT likely, because then the effects would be constant.

2. The actual sencors are damaged somehow. Maybe, but you'd have to be a very amateur mechanic to make this mistake in my opinion.

3. Teeth on the Wheel Speed sensor have been disturbed. I AM 99% certian this is your issue. More than likely one of the teeth on the wheel speed sencor(s) have accidently banged off some other parts and it's giving off a funny reading to the ABS.

If you discover that this is the case, and the Wheel Speed sensors have been infact damaged, your mechanic should be 100% liable since that part has nothing to do with a wheel bearing. Replacement would be best otherwise, you may be able to file and reshape the one or two teeth that have lost their clean square shape.

I know this because that's what happened when I changed out my own wheel bearing. I filed out the imperfection in this case and everything was fine. Also when I bought my A4, one of the teeth whs broken off somehow, replacement was necessary in that case.


thanks rocket...great info.

i think its prolly option 3. that they have been disturbed. vag said front right one...i'm hoping that is the only one.

like i said...i am unaware of anything as i did not attempt to do this install myself. i figure install turbos was easier [:D]. i didn't do the suspension install so i can't say for certain what has happened.

the only thing i do know is that the sensor wasn't on prior to install and the sensor is on now. i will go ahead and talk to the local tuner.

diegomatrix
03-19-2006, 09:15 PM
probably option 1... where the sensor wire has been stretched while removing the suspension. you can ghetto fix the wire if that's the case... (soldering/reinforcing the wires). I would first try moving the wire around abit and then check w/ vag to see if you're getting the correct signals while moving..

clean sensor head is next step

and then do diagnosis for option 3.
you can look through the sensor hole and rotate the ring to check for any irregularities in the teeths.

you can also use vag to log each sensor while you move the car to see if the sensors are working correctly after you perform the checks for each option red listed.

RedRocket
03-20-2006, 04:37 AM
^^^Correct. Also I don't think the your local shop would have taken the hub off the axle, so I don't kow if the speed sensor would be the problem. Probably the reader (or ABS sensor it can be called) is not plugged in right.

b00st
03-20-2006, 07:37 AM
what about for an alignment?

vag says front right speed sensor is bad....why would it be bad? its a little coincidental no? its bad the same day my car is finished with the install. I hoping its an easy fix. Dunno if its not plugged in right...can you see it with the tire removed? or what if i jack the whole car up?

RedRocket
03-20-2006, 07:54 AM
The alignment shouldn't have anything to do with it.

Have you contacted the shop that did the work?

The only ABS component that's involved in a suspension swap is the ABS sensor. The sensor comes from the wheelwell and plugs into the splindle/hub assembly. I'd first check to see if it is still connected. You can do this by pulling off the wheel.

The sensor itself is like a 2-1/2 metal rod that is not visible from the outside. If it's not visible, it can't be really damaged unless the axel was taken out of the hub by your shop. It is not likely they would do this to install a suspension because it is not necessary at all.

So inform the shop of this problem, and/or have a look at it yourself to determine if the sensor is not plugged in right.

If the shop for some reason has DISCONNECTED the axel from the hub and put it back in, there is the chance that the wheel speed sensor teeth have been disturbed. And you will have to go that route.

RedRocket
03-20-2006, 08:04 AM
http://i16.photobucket.com/albums/b21/Redrocket_1981/broken.jpg

There:

A. Abs Sensor, plugged in, top is visible.
B. Wheel Speed Sensor is inside the spindle, I have drawn the amaginary teeth that wiz by the ABS sensor, that reads the metal teeth megnitically, to determine the wheel speed.
C. the ABS sensor wire. Follow it as much as possible. Look for pinches, disconnects, etc.

Also. I am even more certain it's the wire because if it was the wheel speed sensor, your ABS would be acting fucking wacko.

If the light is on, you more than likely have low or NO signal and the ECU detects this as a problem.

beat up Wheel Speed Sensor = wacky readings, but still valid to the ECU. Unless its been totally beat up and the teeth are fucking mashed to shit. once again, this is not likely unless your mechanic is an alcholic.

charlierevell
03-20-2006, 08:13 AM
Its simple mate... when removing the old strut they probably hit the arms with a hammer! This will have dislodged crap in the hub carrier, which will have fallen onto the ring and sensor. Causing duff readings.

Take off the wheel, pull out the sensor, blow out the mount, give the sensor a clean (Brake cleaner or sumthin)
Spin the hub and make sure its clean all the way round.
Rebuild and take it for a spin!!

Exactly the same happened on mine and it all came from breaking the ball joints loose with a hammer.
You dont need to touch the sensor in the install, so it fills with crap easily. As its a magnetic sensor it only takes a tiny amount of metal to stick to it for it to 'SEE' the wheel as stationary. Therefore locked up, and ABS kicks in!

RedRocket
03-20-2006, 08:26 AM
but I don't think his ABS is kicking in. Never-the-less, you're very correct in that crap could have fallen apart within the hub. Only problem is that the sensors are often seized into the hub, making it a real bitch to Re & Re. I've had dealers tell me to remove the ABS sensors that there would be no guarantee the wouldn't break. But that's the dealerships, go figure.

b00st
03-20-2006, 10:14 AM
thanks you guys for the pictures and help.

much appreciated!!

at least i can take a look around now and see whats up. the ABS isn't acting up or anything. everything seems to be fine...i just don't think the ABS works anymore. from what i was told. but braking seems fine. lights are blinking...its just constantly on. i will take a look around and contact the shop.

thanks guys.

b00st
03-20-2006, 11:21 AM
OK scratch that....
now i have no ABS light...but my ABS is outta control on braking...so i'm assuming a bad connection?

the light has gone away and now my ABS is kicking every time i go to brake. so perhaps the harness is not connected fully or a wire is pinched? i can't drive like this.

RedRocket
03-20-2006, 11:47 AM
Originally posted by b00st
OK scratch that....
now i have no ABS light...but my ABS is outta control on braking...so i'm assuming a bad connection?

the light has gone away and now my ABS is kicking every time i go to brake. so perhaps the harness is not connected fully or a wire is pinched? i can't drive like this.

Did you change anything? What happened?

b00st
03-20-2006, 12:08 PM
i did nothing.
i just started my car and went to lunch...my brakes felt funny. i look at the dash. the ABS light is off and my ABS is going off now everytime i brake.
nothing has happened since i drove to work this morning. i just went to lunch and now my ABS is kicking in everytime i stop. so i don't know what to think? pinched wire? why would ABS be going off now and the light has disappeared. now driving sucks.

RedRocket
03-20-2006, 12:12 PM
that's really wierd. Now it's acting like a fucked up speed sensor.

You gotta check that wire out bro. And take it from there.

b00st
03-20-2006, 01:13 PM
yeah and now....the light just turned back on....so now its not going crazy. the light just turned back on as soon as i got back to work as i was parking. it drives better when the light is on....

i wonder if when the light is off that my abs is not braking the car after i hit above 40. feels funny when driving around those speeds...feels like something is rubbing. and the braking is horrible.

i will take it back into the shop. they are fully prepared to take a look at it and deal with it.

charlierevell
03-20-2006, 01:26 PM
ITs what i said mate.... hence the ABS goin crazy. Take out the faulty one clean it up and put it back in.

b00st
03-20-2006, 01:33 PM
you did charlie.

thanks for your input!

charlierevell
03-20-2006, 01:38 PM
hehe.... It just wound me up for HOURS when it went wrong on mine! every time i slowed it felt like a giant Rampant rabit!

b00st
03-20-2006, 01:48 PM
yeah...i know the feeling now!

sucks...but it will get corrected. if i had done the install....i would be more familiar...but i didn't cuz i am TEH LAZY!!!!

but suspensions can be a PITA with the tie rods...so i didn't want to join that fun.

RedRocket
03-21-2006, 07:08 AM
I hope thing are going ultra good for you, and that you're ultra happy now.

EDIT: And that's it's ultra fixed [:)]

Eurasia_1.8T
03-21-2006, 07:31 AM
ABS Control Module. Let's hope not...

b00st
03-21-2006, 10:38 AM
Originally posted by RedRocket
I hope thing are going ultra good for you, and that you're ultra happy now.

EDIT: And that's it's ultra fixed [:)]


i will go back to being ULTRA happy when it is fixed. [up]

for now...is broken.