Brake problem! Loss of preasure...

[Idahosr5]

Brake problem! Loss of pressure...

Twice now while braking and hitting bumps in the road my brakes have lost preasure and the pedal sinks. The second time i noticed a pop sound from the brake controller area when it happed. It old seems to do it if there are bumps in the road, like bridge joints. Its a bit freaky when it happens...they lose pressure but not all braking ability is lost. Are there any know issues with this or TSB's? My guess is a new brake controller is not cheap. The system was checked, adjusted, and filled not to long ago. Fluid level is at max after pumping the system up like the instructions say.

 

[Mauzer]

I haven't seen a TSB for 3rd gen brakes, I would bleed them and see if the problem continues

 

[LittleCaesar]

Has the ABS light come on?

It sounds like you still have air somewhere in the lines. Rebleed them.

 

[Idahosr5]

No abs lights on. I dont think it's air...It brakes fine 99% of the time, and I can slam on them and engage the abs, and it stops well. It's only when I hit a bump that this sudden loss of pressure is occuring.

 

[Nelsonmd]

Could it be your abs kicking in a little bit? when I go over bumps with the brakes on, the ABS seems to half kick in a little bit cause a stumble in braking. Could just be the nature of the beast.

If you can recreate it easily, try disconnecting your ABS and going over the bumps, see if it stops doing the same thing.

 

[Idahosr5]

yes I need to try and duplicate it...and that's a good idea...will disconect the abs and see if it still does it with out locking up.

 

[t4r4life]

most of the time its abs

 

[Idahosr5]

Well I think it is the abs engaging just breifly and then stoping. I think the struts are worn out and the wheel is leaving the ground and stoping over some bumps...

 

[Nelsonmd]

Well I think it is the abs engaging just breifly and then stoping. I think the struts are worn out and the wheel is leaving the ground and stoping over some bumps...

That sounds plausible. Mine did the exact same thing. It will still do it with new suspension, but shouldn't do it as much. I also recommend installing an ABS shutoff switch. That will probably be my next mod.

 

[Nates_NW4Runner]

That sounds plausible. Mine did the exact same thing. It will still do it with new suspension, but shouldn't do it as much. I also recommend installing an ABS shutoff switch. That will probably be my next mod.

An ABS shutoff switch!?! That sounds intriguing... Do you have more information about this setup? I hate being surprised by my ABS system!