Rear left brake doesn´t work right

Hi guys! I´m asking your help to my nasty problem.

I replaced my rear left caliper because old didn´t work (or at least it didn´t get any Nm in brake dyno). Now I have a new caliper at rear left corner, we have bleeded it many times and the piston in caliper moves freely and pads are being pressed into the brake disc as normally. So everything seems fine, but that corner doesn´t have enough brake pressure or something, because I can turn the wheel by hands when brake pedal is pressed. Also hand brake doesn´t work the way it should. :frowning: Front right seems to be strong as hell, so it seems that all pressure goes there from that circuit (left rear, front right).

I have two opportunities; either proportioning valve is broken or my left rear brake hose or pipe is stuck from inside. What do you think? I also noticed that when I push the brake pedal when the car is running, it goes all the way to the carpet. When the car isn´t running I get the pressure and it doesn´t disappear so iI think that brake booster and master cylinder are ok then.

Do you have any idea or solution to my problem, how to get pressure again to that rear left wheel? :hmm:

Bad Breaks…

I’ve never had that happen to me, but it sounds like you’re on the right track.
I’d get a proportioning valve from a junk yard and bleed the breaks real well.

When you’re bleeding that bad one see if fluid is coming out at a normal rate. If it’s slower then your other breaks, you probably have something stuck inside the line.

In that case unhook the line and blow it out with compressed air. That’s what I would do.

Fil [:slight_smile:

Hi again! Fluid came out with a normal rate, so I didn´t replace brake hoses or pipes at all. And it seems that there is enough pressure also, because fluid comes as fast as in other brakes too. Still I can spin the wheel by hands (roughly) when the pedal is pressed down. With handbrake on it´s so tight that I can´t spin it, but it´s still weaker than the other side, it´s easy to notice on a sand.

I don´t know what to do anymore. :frowning: Have to go to brake dyno to see what really happens there…

It showed that all was fine at brake dyno. :slight_smile: So happy ending! :smiley: I don´t realise how it´s possible that you can spin wheel when brake is pressed, but what the f*ck, if it´s ok at the dyno so then it´s fine. :slight_smile:

id say the reason you can turn it (roughly) when your normal brake pedal is pressed is because when you use your normal brakes it only brakes partially in the rear. therefor thats why when you use your hand brake its stiff as hell and can’t turn. :slight_smile: i may be wrong on this but thats my opinion…