brake problem when holding the brake

[thrasherguy99]

ok guys could use some help. on my 89 accord lxi when im say in a parking spot holding the brakes, the pedal just kinda slowly goes to the floor and once its there if i let off even a centimeter the car starts rolling but once i start driving it's fine. even pumping the brakes does nothing. but its only holding them for a long period of time that it does that. and the reservoir is full.

[conozo]

Hi, We just had someone else with a brake booster problem in another thread scratching-my-head-brake-booster-troubleshooting

I think you have a failing brake booster. To test you need to get a vacuum pump and see if the booster holds a vacuum. Also in the shop manual which is available here on this site by search, will give you diagnostic tests to preform.

[gp02a0083]

as Conzo mentioned i would get a vac gauge to confirm that the booster is holding. it is also a possibility that there is air or a leak in your system.

[Dr_Snooz]

This is classic master cylinder failure.