Cycle ABS for brake bleed? Vx commodore.

[vx_commodore]

Hi all.
I need to bleed my brakes on my vx commodore. It has ABS.
As I have just changed my master cylinder.
I believe there is air trapped in the ABS module. And it needs to be cycled to get any air out.

Ever since I first bleed my brakes years ago, The pedal goes down quiet far. I believe this is due to air in the module. There is definitely no air in the lines. I made sure of this.

Is there any way using the obd cable and software, To cycle the ABS to get any air out?
Or can this only be done via a high-end scan tool?

Thanks!

[Charlescrown]

I am surprised you had a problem I just changed one today on a VY and had no issues at all. My method is probably a bit primitive but if you take the car for a drive and brake hard making the ABS operate it should push the fluid/air around to then allow you to bleed it successfully.

[pman92]

Have you tried bleeding it with the new master cylinder anyway?
Very possible the original master cylinder was corroded, and when you bled it originally the extra piston travel had damaged the cups and created a low/spongey pedal.
Now you have a new master cylinder it will be fixed.

It's a risk every time you bleed brakes on older vehicles, especially that haven't had regular fluid changes, unless you vacuum bleed or pressurise the reservoir.

Also check brake hoses etc arnt ballooning.

And pump out the booster vacuum. If the pedals nice and hard then it's probably not air at all.

While not impossible I think it's unlikely there's air in the ABS modulator. It would theoretically have had to have air in it and then have the ABS operate to get it stuck in there.

[Dylan]

Aren't the ABS module ports normally opened? Unless there's a wheel locking situation?

[Gareth]

Yep

[Dylan]

Wouldn't of thought bleeding would be any different to non abs.
I've it o few times on abs cars without problem.

[The1]

vac is the only way to go, i had done it various ways for years, after picking up one of these the other day on special $70 locally did my brakes, VS ABS, best theyve ever been.

https://www.kincrome.com.au/vacuum-one- ... ke-bleeder

[vx_commodore]

Pedal has always gone about halfway down to floor. As far as I remember it has always been this way.

When I purchased the car, the engine was blown. So while changing engine, I bleed the brakes. So I never got to feel how it was before my bleeding.

As the brakes have always gone down so far(which is really dangerous) I really wanted to get it back to normal. So I have bleed it about 15 times. But still the same.

Once pedal is halfway down, It brakes nicely. Seems firm-ish

I have checked and adjusted the booster push rod, That is all fine.

There is absolutely no air in the lines. Yet excessive pedal travel. I had a read around and many have mentioned possibly air in ABS module. So this is my next focus, Really hoping this is the answer as it is annoying/dangerous having such travel.

As I have removed/replaced the MC a few times, I thought its very possible that air could have got in and has pushed it and trapped it in the module.

I have tried the wet grass lockup and bleed a few times, But can't say for sure if this method even does anything. Probably not.

All MC's have been the same excessive travel.

So, my last hope is that there is air trapped. And if it was possible I would like to try get it out(if any)

If not. Then it just must be the car? But half way to floor is too far!
Other commodores I have driven did not do this....I guess this is why I hold hope in air trapped. I can't really see any other reason.
All metal lines and rubber pipes are in very good condition.

[The1]

where you located?

[vx_commodore]

vac is the only way to go, i had done it various ways for years, after picking up one of these the other day on special $70 locally did my brakes, VS ABS, best theyve ever been.

https://www.kincrome.com.au/vacuum-one- ... ke-bleeder

Yeah, I think you're right.
I have always done my own mechanical work, Worked as a mechanic hand for a few years. And the one time I paid a mechanic for work. They absolutely did a horrible job. Wrecked everything!

But for this, Its not worth buying the tool for a 1 time job.

Just thought I'd check to see if I could cycle the ABS myself. So I could try. But as I can't. Think I'll just pay for it to be done via a vaccum. I agree this is the best method.

where you located?

Sunshine coast QLD.