i have a 2004 monte my brake pedal pumps up in down under normal braking conditions its like tha a.b.s is stuck on can you help me?

 

does it do it all the time, or once ina while? does it do it at all speeds? or just low speeds, or coming to a stop? brake or abs lights on, or ever been on?

 

yes it does it all the time and at all speeds and stoping since the problem ocured i thaught maybe it was a warped rotar so i did the front brakes butit was still there made sure every thing was really clean no shake in stering wheel. no abs light ever

 

kinda stumped i guess.... any work done shortly before this happened? all tires the same size? any mods, especially tires/wheels/suspensioin?

if nothing to suspect so far i'd try getting it scanned to make sure theres no codes for the abs.

 

well i think im going to change the rear disc and see if the problem is still there and if it is i will get it scaned thanks for the reply 2000ls

 

I wonder if a shot sensor would cause this... maybe a sensor is reading that your tires are locking up?....