95 ABS

[boregard]

I am having a problem with my ABS after replacing the front rotors. The system causes brake "chatter" or "grab" especially at low speeds. I can pull the fuse and the problem goes away. The problem started after I changed the frond rotors and pads.

When I changed the pads, I did not drain the brake resevoir and used a "C" clamp to push the pistons back into the caliper, which also caused the resevoir to overflow. I was told that in doing this I caused damage to the ABS control valve. I was told that I should have loosened the brake lines and opened the bleeder screw.

Can anyone confirm what I have been told?

boregard

 

[mrboyle]

There is a possibility of this occuring, but I have never seen it happen. You might want to check your ABS sensors on the front for build up of metal shavings. The magnetic sensors attract metal and if enough is built upon the end of the sensor it will produce errratic readings.

 

[boregard]

Mike,
Thanks for your reply. I have determined that what I was told probably refers to plugging the brake lines if the caliper is removed for service. If the lines are not jplugged the ABS control would have to be bled, which I understand is quite complicated, requiring a lot of expensive tools.

I found that the left front rotor ring was not peroperly seated in the rotor and was causing the problem with the ABS system. I replaced the rotor, ensuring that the ring was seated all the way and the problem seems to be solved. I still have a very slight chatter once in a while, but not nearly as severe as before. I highly rcommend that anyone check the ring before installing the rotor.

I am concerned about the sensor on that wheel because a slight amount of meteal was shaved off by the ring. I do not know how much metal can be removed without affecting the ability of the sensor to send the proper signal to the computer.

Boregard