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Brake issues- soft pedal ***updated with video***
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Onlinebigwinn
- Lifer
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Brake issues- soft pedal ***updated with video***
Hi all
So a new issue with the project to sort
The brake pedal is very soft. Will go to the floor with minimal resistance. However with a few pumps it tightens up to how you’d expect.
New fluid and full bleed including ABS bleed
New hoses
No leaks
New master cylinder
Any thoughts what to check next?
I would say vacuum leak but I took the master cylinder off today after the car sitting overnight and there was a good amount of residual pressure in the system.
Thanks in advance chaps
Stuart
So a new issue with the project to sort
The brake pedal is very soft. Will go to the floor with minimal resistance. However with a few pumps it tightens up to how you’d expect.
New fluid and full bleed including ABS bleed
New hoses
No leaks
New master cylinder
Any thoughts what to check next?
I would say vacuum leak but I took the master cylinder off today after the car sitting overnight and there was a good amount of residual pressure in the system.
Thanks in advance chaps
Stuart
Last edited by bigwinn on Sun May 26, 2024 10:44 am, edited 1 time in total.
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- enuff_zed
- Lifer
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Brake issues- soft pedal
Well now you mention residual pressure I am leaning back towards an air lock.
Forgive me for the daft question but have you definitely got the pipes on the abs unit in the right order. I know there are two different sizes so can't really go that wrong.
Do you have any ABS/DSC codes?
Forgive me for the daft question but have you definitely got the pipes on the abs unit in the right order. I know there are two different sizes so can't really go that wrong.
Do you have any ABS/DSC codes?
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Brake issues- soft pedal
If it’s not leaking and you have check the vacuum. Then it must have air in the system.
2009 09 Carbon Black Cinnamon E86
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Onlinebigwinn
- Lifer
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Brake issues- soft pedal
No codesenuff_zed wrote: ↑Wed May 15, 2024 5:31 pm Well now you mention residual pressure I am leaning back towards an air lock.
Forgive me for the daft question but have you definitely got the pipes on the abs unit in the right order. I know there are two different sizes so can't really go that wrong.
Do you have any ABS/DSC codes?
And yes I did originally get the pipes the wrong way around
But at least I’m fessing up to that
So a damn good bleed needed we think?
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Onlinebigwinn
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Brake issues- soft pedal
Roger that
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- enuff_zed
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Brake issues- soft pedal
bigwinn, to confirm, when I did mine I started rear right, then clockwise round the car to the front right last. That was a conventional bleed, with the pressure bleeder, but not activating the ABS.
Then did the ABS part repeating the four corners in the same order.
For each corner I ran the abs pump twice.
If it helps, I counted ten pulses of the pump in eight seconds every time.
Then did the ABS part repeating the four corners in the same order.
For each corner I ran the abs pump twice.
If it helps, I counted ten pulses of the pump in eight seconds every time.
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Onlinebigwinn
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Brake issues- soft pedal
Cheers Martin
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- Lifer
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Brake issues- soft pedal
I had a similar problem with OBY after changing the brake pressure sensors. Not much fluid came out, but I must have let some air in nevertheless. I followed Martin’s bleeding guide, but with an extra hand topping up the reservoir, rather than a pump. It worked a treat.
2003 Maldives Blue 3.0i auto
Previously: Maldives Blue 2.5i manual (its back!) and another, and a Monaco Blue 3.0Si coupe
Previously: Maldives Blue 2.5i manual (its back!) and another, and a Monaco Blue 3.0Si coupe
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- Lifer
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Brake issues- soft pedal
In fact I didn’t run the ABS, just did the manual bleed cycle twice.
2003 Maldives Blue 3.0i auto
Previously: Maldives Blue 2.5i manual (its back!) and another, and a Monaco Blue 3.0Si coupe
Previously: Maldives Blue 2.5i manual (its back!) and another, and a Monaco Blue 3.0Si coupe
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Onlinebigwinn
- Lifer
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Brake issues- soft pedal
Thanks Ben
I’ll give it a good pump (fnarr fnarr)
I’ll give it a good pump (fnarr fnarr)
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- enuff_zed
- Lifer
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Brake issues- soft pedal
If you don't disturb the ABS unit you can just do a normal bleed.
- enuff_zed
- Lifer
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Brake issues- soft pedal
Stuart, if it turns out to be air I shall tell everyone you are 'bleeding' useless.
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Onlinebigwinn
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Brake issues- soft pedal
I’ve been called a lot worse
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Brake issues- soft pedal
It’s possible to get air stuck in the calipers, even a thorough bleed doesn’t always shift it. Bleed while clouting the calipers with a rubber hammer has been known to shift an air lock.
M roady...OEM CSL’s, strut brace, Remus back boxes, ZHP
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E89 35i project car...mapped 365bhp, M4 stoppers & wheels, KWV3’s, H&R front ARB, M3 front arms, strut brace Eisenmann cat back race exhaust, VRSF downpipes inbound
E89 35is
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MR2 MK 2
E89 35i project car...mapped 365bhp, M4 stoppers & wheels, KWV3’s, H&R front ARB, M3 front arms, strut brace Eisenmann cat back race exhaust, VRSF downpipes inbound
E89 35is
G29
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Onlinebigwinn
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Brake issues- soft pedal
Bearing in mind one calliper and all lines are new too
Cheers John
Cheers John
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