Brake issues

[nielsc]

I have this problem with my brakes for some days and I can’t figure out what causes it.
When I press the brakes, i have to push the pedal quite deeper then before, and when I press it hard my 80 gives a pull to the right, also noticable in the steering wheel, it is only for a second, then it brakes straight.
Then driving along the brake pedal feels nice and firm as it should untill the next kilometer or so, then it’s the same again.
Front and rear left brakr calipers are new, front brake pads are new.
Rear brake pads are new.
The rear left brake disc is somewhat grooved, but was also before the probles started.

Another very weird issue, when I pump the brakes up with the engine running, as the pedal gets hard the engine glow light comes on and goes away as the pedal drops ????


Any ideas ???

 

[Chris]

Very hard to nail this one in one go. I'd suggest it's not an issue with your calipers, disks or pads. I experienced something very very similar to this recently on someone else's 80 and it was the ABS system. OFrom setting off, all seemed fine then when braking it pulled violently to one side then seemed to straighten up and the ABS fault light came once we put new sensors in and changed the CVs it was like new. We pulled the ABS fuse too and drove it like that for a while and it was fine. ONly thing that's different here is the engine glow light symptom.

Worth pulling the ABS sensor, give it a clean and inspect. Pop it back and then see. Next, remove the spacer shim on the sensor and lower the sensor closer to the ABS ring perhaps.

Also I'd certainly read the fault codes by shorting out the diagnostic plug under the bonnet and see what that tells you about stored codes.

 

[nielsc]

Sorry, I forgot to mention, the ABS fuse is removed for the issue you mentioned.
I think what you mean is that the ABS kicks in and loosen the brakes on one wheel.
This is not the case because the fuse is removed.
Regards

 

[Chris]

Errm, no it isn't.

 

[nielsc]

Errm, no it isn't.

Okay... but it can’t be the ABS as it is already disabled ? Or a I missing something ?

 

[Chris]

OK we're at crossed purposes here. You didn't mention you'd pulled the ABS fuse in your first post. We had exactly the same symptoms as you described and it was the ABS sensor. I did not say the ABS kicked in - it didn't. The steering just pulled violently to one side - so I meant exactly what I said.

Now, you're having something that sounds the same but can't be. Hmm, I might suspect the seals in the master cylinder. There are two seals as the braking system is split. It's possible (especially in this cold weather) that the seals are getting very old and sometimes they work and sometimes they don't leading to uneven braking and deeper pedal travel. If the seals didn't work at all, you'd crash. But if one set worked, you could get some odd results. That would perhaps be my first place to look if you are confident that the brakes at the wheels are OK.

 

[Gary820]

Play in a wheel bearing pushing the pistons in a bit on one side? Giving you the initial poor pedal/pulling then the same again after driving a km.

 

[nielsc]

Play in a wheel bearing pushing the pistons in a bit on one side? Giving you the initial poor pedal/pulling then the same again after driving a km.

I'll check them tommorow, but all were replaced or adjusted a while ago.

 

[joinerman]

X 2 on what Gary said above.

 

[Dave2000]

Play in a wheel bearing pushing the pistons in a bit on one side? Giving you the initial poor pedal/pulling then the same again after driving a km.

Just given the OP this advice over on MUD as it was posted there as well, it does sound like pad knock off.

Regards

Dave

 

[nielsc]

Just given the OP this advice over on MUD as it was posted three as well, it does sound like pad knock off.

Regards

Dave

I’ll check wheelplay tomorrow.
Since it pulls to the right I suspect the problem should be at the left side.
I replaced the rear left a couple of months ago and had to adjust it already a while ago, so I’ll look there first.

 

[nielsc]

The front left wheelbearing got loose completly. Again
Tightend it and all is good now

 

[Gary820]

Result, seen it a few times at work.

 

[Chris]

Well there's another lesson in never assuming that the obvious stuff has been checked first.