Spongy brake pedal

[bigjeeze]

Hi Guys

I changed my front brake pads and for the first time I didn't release the bleed nipple and just pushed the pistons back in. Once I fitted the pads I had a very spongy pedal, so I bled the brakes ( 3 times so far) but to no avail. So I thought that perhaps the dread flipped seals was the issue. I have to say that I have never seen this or heard of anyone having it but I thought sod it I'll replace the MC.  I managed to get a new one and it arrived today, I fitted it bled it 3 times but I still have the spongy pedal which slowly sinks to the floor once the engine starts.

I can only think it is air in the ABS block . Has anyone any ideas or solutions - I am getting really fed up now!!

[KingyMAK]

Sounds stupid, but did you bleed it in the correct order?

[johnnyroper]

When bleeding has all the air stopped being expelled?

Prior to bleeding right after pad change did pedal sink to floor or was it just spongy? New pads are spongy until bed in especially if disks not in best of shape.

Might be worth clamping flexi Hoses 1at a time to see if that makes a difference and if you can pin it down to a particular side.

[bigjeeze]

Hi Gents
Thanks for coming back to me.

I was always told to bleed furthest from the MC first. But I read on a forum that Galaxy's should be bled nearest first. So I have tried it both ways - no difference.

I have completely changed the brake fluid- some 2 litres.

When I fitted the pads - it felt fine until I started the engine then the pedal started to sink. That's what made me re bleed and change the MC.

I have also read that some people advocate taking the car somewhere quiet and jamming the brakes on to shift any air in the ABS pump. I'm not sure that's a good idea. What do you think?


BJ

[Ben g mon]

Be interesting to hear the answer as under the new mot rules my black brake fluid would fail. Was going to ezzibleed pressure change it at 12psi so Iââ,¬â,,¢m keeping an eye on this for avoidance on master seals flipping !

[johnnyroper]

Is the pedal worse than when you originally had the issue? It might be worth driving somewhere quiet and seeing if it improves.

As for the black fluid I would suck it out of resavoir with syringe or alike and refill with fresh fluid,then give each corner a bleed. Personally donââ,¬â,,¢t use pressure bleeders I just gently pump pedal with the help of an assistant on the bleed nipple. Not had any problems with seals flippingas yet.

[bigjeeze]

[/quote]

Hi Gents
Thanks for coming back to me.

I was always told to bleed furthest from the MC first. But I read on a forum that Galaxy's should be bled nearest first. So I have tried it both ways - no difference.

I have completely changed the brake fluid- some 2 litres.

When I fitted the pads - it felt fine until I started the engine then the pedal started to sink. That's what made me re bleed and change the MC.

I have also read that some people advocate taking the car somewhere quiet and jamming the brakes on to shift any air in the ABS pump. I'm not sure that's a good idea. What do you think?


BJ

So far I am still unable to bleed the brakes and remove the spongy pedal.  I had a wheel sensor go faulty - which I have replaced but it still shows as faulty. Do I have to use VCDS to remove the fault or should it automatically reset?
Does no one have any idea as to what I can do to fix this?  To activate the ABS pump to get rid of air needs a full copy of VCDS  which I don't have.

Any suggestions?

[johnnyroper]

If fault has been rectified it should self clear,may need to be driven a short distance.

Might be worth seeing if anyone local has registered copy to activate ABS for you see if that helps

[bigjeeze]

Thanks Johnny

I don't know anyone local with a copy.

Cheers


BJ

[johnnyroper]

Not ideal but I had similar issues gaining a pedal on my old x type jag,I ended up cracking pipes 1 at a time at ABS pump to bleed then did a full all round bleed again.

After you fitted the pads was pedal ok until you started engine? Could it just be spongy due to new pads on old disks? Have you tried clamping flexi hoses to see if pedal returns to normal?

Apologies I have not read back through thread so canââ,¬â,,¢t remeber what you have tried already

[sparky Paul]

First of all, I agree with johnnyroper 100% about Eezibleeds and other pressure bleeders, they are nothing but trouble. I bought one nigh on 30 years ago, and never used it again - you have to be very careful indeed to avoid putting air into the fluid. Either use the two man method, or invest in a vacuum bleeder.

ABS sensor faults should clear themselves over 15mph if all is well. If you find that the fault still exists after replacing a faulty sensor, the corrosion on the caliper may not be allowing the new sensor to seat properly. Remove the sensor and clean the scale off the caliper before refitting.

The Galaxy brake hydraulics are a bugger if you get air in, it can take some shifting. If it is in the ABS block, it won't come out without performing the full bleed procedure using the ABS pump and VCDS.

Some have had success with the 'stamping on the brakes to activate the ABS multiple times' method, but there's no guarantee you will get all, or even most of the air out. What happens is the shock from the ABS actuators breaks up the air bubbles into smaller ones, so that it's easier for them to be bled out of the ABS block. You still then have to bleed immediately to stop the smaller bubbles combining again.

[bigjeeze]

Thanks Paul.

I have now obtained a vacuum bleeder so will try that and see what happens.

[bigjeeze]

What a waste of time! The vacuum bleeder sucked in tons of air via the nipple threads - absolute crap!!

[johnnyroper]

I have only used a vac bleeder after pipe change etc to get the fluid down to caliper initially,I donââ,¬â,,¢t think there is any substitute for the 2 man bleed like the old days.

Did you ever try clamping flexi hoses to get it down to a problem with fronts or rears?

[christiant]

An old trick I personally use but you need a compressor. I have successfully bled mine using a modified cap on the tank, which has a mounted threaded tire valve on it. Just get one from breakers, drill trough the middle of it and remove the fluid level sensor, you might need to use some sealant as the bit in the middle is a bit loose. Just screw the valve tight in the whole. Screw it on the brake fluid reservoir and  apply very light air pressure to it and undo the bleed screws one at a time staring at the furthest one, gets rid of the old fluid quick and its a one man job. It definitely works really well and those vac things are a waste of time unless you have a professional one which costs a fortune.