ok so, my brakes suck. lol when u push in the pedal, its firm at first, then slowly goes to the floor, u pump it twice, and its firm again, but will fall.

Now, if im on the highway, say doing 70 for 5 miles, when i get off the highway, my brakes are great, firm pedal, no dropping, etc, as soon as i stop and move again, brake pedal starts falling again.

Now the weirdest issue.

i noticed this while sitting at taco bell, my idle will drop relatively low, say 800 rpms, but if i pump the brakes a few times, My idle will rise to about 1500. if i quit pumping the brakes, the idle will fall again..

any ideas will be awesome.

 

master cylinder.

 

master cyclinder or brake booster...if ur brake booster is leaking it would cause the low idle when u step on the brakes....if ur master is bad it would cause u to have to pump it for it to hold....also there is a seal in between these 2 parts and if that went out then it could cause both issues....first thing i would do is change out the master and if ur idle still drops when applying the brakes at idle than replace the booster also....1500 rpm is way high for that car i think its suppose to be like 700-800