Soft brake pedal after new discs & pads

[nickbw]

I agree will all the above. However, having changed both front and rear disks (rotors) and pads in the last 12 months, it has been my experience that a correctly adjusted handbrake (which works ion the drum shoes not the disk pads) never the less affects the brake pedal feel, which is firmer on correct adjustment. Having said that I agree with Bill the pedal is nothing like as firm as Porche. What matters most is stopping power and with good disks and Akebono Ceramic the car will stop fine. The handbrake mechanisum needs to be lubed and can be a cause of serious problem including hub damage if not regularly serviced.

[vtl]

In case air bubble traveled up the brake line far enough it may get trapped in ABS module. Regular bleeding won't push it out of there since there's no fluid circulation under normal conditions. I was fighting with weak pedal for about 3 years, bleeding with Motiv at 3 BARs didn't help. What helped is ABS valves modulation via DiCE+VIDA, that escaped a lot of air. Brakes bites quite well since that.

[billr99]

In case air bubble traveled up the brake line far enough it may get trapped in ABS module. Regular bleeding won't push it out of there since there's no fluid circulation under normal conditions. I was fighting with weak pedal for about 3 years, bleeding with Motiv at 3 BARs didn't help. What helped is ABS valves modulation via DiCE+VIDA, that escaped a lot of air. Brakes bites quite well since that.

I haven't seen this in VIDA yet, but you are saying you can trigger the individual ABS valves via a signal from VIDA and thus apply the brake calipers individually? Man, if you can do that, that would be helpful at times.

Cheers,

Bill

[vtl]

I haven't seen this in VIDA yet, but you are saying you can trigger the individual ABS valves via a signal from VIDA and thus apply the brake calipers individually? Man, if you can do that, that would be helpful at times.

Cheers,

Bill

Yes. Start bleeding with Motiv under good pressure, you need a full jug of DOT in it, maybe more. Brake pedal depressed and fixed, etc. Then in VIDA go to diagnostics -> vehicle communication -> BCM -> activation. Each wheel has inlet and outlet valves, forgot which one applies or releases pressure. I triggered both few times, all air escaped via one corner, the rest were air-free.

[billr99]

Yes. Start bleeding with Motiv under good pressure, you need a full jug of DOT in it, maybe more. Brake pedal depressed and fixed, etc. Then in VIDA go to diagnostics -> vehicle communication -> BCM -> activation. Each wheel has inlet and outlet valves, forgot which one applies or releases pressure. I triggered both few times, all air escaped via one corner, the rest were air-free.

By "full jug" do you mean the brake reservoir or the Motiv? If the latter, that's a lot of fluid!

Thanks for the instructions, going to try it next time I need to bleed brakes. Just got done doing the R and with its 8 bleeders, it was a bit of a chore. This procedure would have made it way easier by the sound of it.

Thanks again,

Bill

[vtl]

By "full jug" do you mean the brake reservoir or the Motiv? If the latter, that's a lot of fluid!

This



Motiv goes through it quickly when the pressure is above 1 BAR and you are on the other side of the car toggling ABS valves in VIDA.

[Kiwirst]

I still don't have the VIDA tool yet & I am thinking about flushing the fluids.

Knocking has since disappeared, I suspect that the left rear hub is slightly out of round as there was a high spot when rotating the disc through the caliper so my assumption is the leading edge of the pads have now worn in to adjust.

[AutosDirectFlorida]

Am I correct in reading this thread that the brake bleed still hasnt been done?

That should of been step #2 after replacing the pads/rotors regardless of assumed necessity.
IMO, its just what you do as a part of that brake job.

[Kiwirst]

Yes, you are correct, a bleed has not been done. I plan on doing this when I can find the time to flush & replace brake fluid