Weird Vibrations and ABS Coming on

[macoman69]

Ive noticed two things with the new installation of my brakes and if some of you could shed some light whether this is normal or weird would really help.

At speeds of 100km/h and up my steering wheel starts to vibrate and when i step on the brake it still seems to vibrate for a while and then calms down?

Also ive noticed on a couple of occassions when going over speed bumps in shopping centres that sometimes the abs kicks in after ive gone over the bump? Is this normal (Keep in mind im going over the bumps slowly)

[JasonGilholme]

Sounds like you knocked one of the wheel speed sensors while you were installing the brakes.

Just make sure you haven't and that the discs are all nice and tight.

other then that you might need to balance your wheels or get an alignment but i can't see how installing new discs/pads could cause that.

Jase

[macoman69]

i didnt even know there was a wheel speed sensor???
It was new calipers and discs installed if this makes a difference?

Could you explain the wheel speed sensor

[JasonGilholme]

i know that i've got (had) wheel speed sensors on the CRX. They were at the bottom of the hub. mugh be in a different place on yours tho.

They basically tell the ABS control module how fast each wheel is spinning so it can engage the brakes and the desired corners to straighten the car up.

They might be out of alignment or something which means the ABS module might be initiating the ABS because its not gettinga reading from that wheel.

hope it helps. I'm not an expert on this but its a little bit of common sense/knowledge that i've picked up along the way.

:thumbsup:

[macoman69]

Where could i get this problem rectified?

[JasonGilholme]

if it is the ABS i'd reccommend honda. Don't wanna get it wrong if its the ABS.

Quick TEMP fix for you tho. you could always disconnect the ABS module. You won't have any ABS but it won't engage on you at random times (which could be even more dangerous then not having ABS at all)

[macoman69]

Thats the funny thing tho it has never done it at high speeds???
Only in the carpark when im going over a speed bump lol

[JasonGilholme]

maybe the sensor is just loose and when you go over a speed bump its moving??

Stick your head under there and have a look. it might just be a case of doin up the mount properly. You should be able to follow the wiring that goes to the hub.

[euGeR]

Did you try and break your pads in?

There's so wear in pattern that you can use. I'll post it up if I can find it. Basically it's something like

6 x brake from 100 - 80km/h
8 x brake from 140 - 80km/h
8 x brake from 120 - 20km/h


When I had my pads first installed, they would shudder under brakes. After i broke them in, they were ok within the day.

[macoman69]

they arent new pads

[destrukshn]

so what did you change?

[CTR Coupe]

maybe the sensor is just loose and when you go over a speed bump its moving??

i broke an ABS sensor when installing my coil overs when the ABS computer loses telemetry(the sensor no longer sends information) from the wheels it turns ABS off all together. sounds more like theres a problem with the brakes and they are locking up.

please explain what your new brakes are. it could be a brake bias problem if you have installed larger brakes(the abs lockup problem)
without knowing your setup its hard to determine a problem.

the vibration braking above 100 is warped rotors.

[macoman69]

Spoon Twin Block Calipers with DBA Rotors (including braided lines and endless pads)

[JasonGilholme]

i broke an ABS sensor when installing my coil overs when the ABS computer loses telemetry(the sensor no longer sends information) from the wheels it turns ABS off all together. sounds more like theres a problem with the brakes and they are locking up.

please explain what your new brakes are. it could be a brake bias problem if you have installed larger brakes(the abs lockup problem)
without knowing your setup its hard to determine a problem.

the vibration braking above 100 is warped rotors.

The thing is the sensor is probably still plugged in, just mis aligned and not reading correctly. Therefore the ABS computer may think there is a situation occuring where ABS is needed, and engages itself.

Also, if the sensor was disconnected/broken the ABS light comes up on the dash ALL the time, not just temporarily/sporatically.

[CTR Coupe]

have you changed anything in the rears? you should probably fit similar rated pads in the rear as this could be throwing out the brake balance and locking the rears.
its sounds like a very strange problem without experiencing it myself its hard to diagnose.

Jason your right the sensor is probably worth investigating but they are not exactly something that are difficult to align or easy to knock out of alignment.

i think at the end of the day you will have to take it to a professional brake place. somewhere that deals with high performance brakes or has some experience with them.

the vibration is under brakes or its when your on the freeway just driving normally.
under brakes its warped rotors
if its not when braking its a balance issue. either the wheels have lost some weight(the little pieces of lead stuck to the inside of the wheel)
or the wheels are bent
or you aren't using hub centering rings(plastic/steel rings that fit between the after market wheel center and your hub to make a tight fit)