Brakes feel "loose"

[valex9499]

I just changed my rotors and pads about a week ago, and they don't seem to hold so strong. I have to press the brake pedal more than half way to get them hold some what good. I bleed the system and no sign of air. Does anyone know what could be wrong? maybe the master cylinder? I appreciate any input.

Valentin

[JCL]

Sounds like you could have air in the system.

Did the level in the master cylinder ever get down to the point that it might have drawn air? If so, you can have air trapped in the ABS controller that won't come out with regular bleeding at the calipers. The BMW procedure is to use a computer to cycle the ABS valves while you are bleeding it. Not really a cheap or easy fix, if that is what it is.

[Dking05]

I'd vote for air in the system... BTW, are the pads OEM?

If your pedal is practically on the floor and your braking power is really poor, then the master cylinder is bad. A soft/mushy pedal can be caused by air in the system.

Slight thread jack:
I have a similar problem as well where my pedal travels more than it should (longer than normal travel / good braking force), but my Master cylinder is new, on rare occasions though my pedal at firms up and works like it should. (short travel / great braking force.) Any idea on what can do that? INDY says the DSC precharge pump, but i'm iffy about that. [Note] Problem isn't booster related.

[SlickGT1]

Ever tried bleeding with car running. I suggested it to another person, and they said it helped.

[TwinTurboGTR]

Yeah, I concur. Either air or you don't have the caliper secured to the supporting bracket.

[valex9499]

Thanks for all the advise guys. I will look into the problem this weekend.

[valex9499]

Originally Posted by Dking05

I'd vote for air in the system... BTW, are the pads OEM?

If your pedal is practically on the floor and your braking power is really poor, then the master cylinder is bad. A soft/mushy pedal can be caused by air in the system.

Slight thread jack:
I have a similar problem as well where my pedal travels more than it should (longer than normal travel / good braking force), but my Master cylinder is new, on rare occasions though my pedal at firms up and works like it should. (short travel / great braking force.) Any idea on what can do that? INDY says the DSC precharge pump, but i'm iffy about that. [Note] Problem isn't booster related.

The pads are from Advanced, they are ceramic pads. Could that be the problem? I think so too that the master cylinder is bad.

[TwinTurboGTR]

Normally a bad master cyl gives a spongy feel and the pedal eventually goes to the floor. I dont think that is the problem.

[Dking05]

Maybe the TIS can help? BMW TIS - 34 90 ... Troubleshooting the brake system

[pnoyako85]

this happened to me......drove it for about 1week by the 2nd week..it was back to normal...i think you feel that the pedal when you brake feels to deep?.....like almost touching the floor?>....if thats the case...just let it break in i guess.....and it will set back to normal....give it time......btw...try double tapping the brake..you may feel a better brake feel the 2nd time.......i did this for a week....and went to normal after breaking in the pads n rotors..