Thanks for thrusth at Just Answer.
Your problem is at antilock brake system,
this is an common fault at one of the wheel speed sensor
you must check this with an scanner and select abs module
then you must check the speed sensor at each wheel
the 4 speed sensor must have the same read
if some is different you must replace the sensor or check what is happens on this wheel
when an different speed value is reading this cause an pump action when is not required
im online if you have some question
if not please dont forget to give me a positive feedback =)
have a good day, best regards.
Thank you fo. Your help . I forgot to say that my car is a 2001 911c4s . My car is at a garage now but they are saying that the computereddies not have a problem in its memory for the Antilock brakes . They have suggested I change the discs and pads . I don't agree because the problem was a pumping and not a vibration but they cannot get it too happen . Any more advice please ??
exactly my friend, this doesnt store a fault code, for this reason i tell that you must see the speed values and check what is the different from the others, them you must replace or check what is happens ot this wheel, this problem wont comes from disc or brake pads, have a good day, dont forget to give me a positive feedback =)
Hello again thanks for your help .i asked the garage if they had done the test that you told me about and this was the reply ....
REVISAR COMENTA EL CLIENTE QUE AL CIRCULAR Cargo a Cliente 28/08/2012 MUY POCO A POCO Y FRENAR EL VEHICULO HACE COMO UN BALANCEO Y RUIDO, EL MECANICO LO HA PROBADO Y TIENE DISCOS Y PASTILLAS
DELANTEROS DOBLADOS, EL CLIENTE QUIERE QUE SE LE HAGA DIAGNOSIS Y SE REVISE EL SENSOR DE VELOCIDAD. .....
Do you think this is a reasonable response .