A3 8PA rear left brake dragging

Hello everyone,

My A3 is causing me concern. The rear left brake is slightly rubbing and getting hot.

I'm used to cleaning the brake pads once a year. With this routine, the first set of discs and pads lasted around 193,000 km. Unfortunately, that didn't help this time. So, I bought and installed new brake calipers. Still no success. Then I installed new discs and pads. Not successful.

I'm running out of ideas now. HBZ? I'm going to completely disconnect the handbrake cables today, but they looked fine to me.

Are there any ideas? When bleeding, a steady stream comes out, and this is the case for all saddles.

Regards,
brezelmann01

...one more question: The pads and rotors are new, and I've only driven 50km so far, barely using the brakes.
Now, both sides are warm/hot. Estimated speed of around 50 degrees, completely without brakes, after traveling 25 km at a speed of 100.

"Could it be that the current heat is due to the initial grinding process?"

Regards,
Brezelmann01

Hi,
Since you're writing about handbrake cables, I assume you're referring to the self-adjusting handbrake system, similar to the one in my old Audi 80. Have you always been retracting the pistons? After swapping the brake pads, you should naturally check the adjustment of the handbrake cables.
hg
Herbert.

Hello,

I seem to recall reading something about swollen brake hoses leading to the caliper in this forum a few years ago.
Apparently, this is supposed to cause residual pressure to remain in the brake cylinder, which can lead to the brakes overheating.

Okay, I'm ready. Please provide the German text you want me to translate.

Best regards, Rainer.

Hi!
Yes, I would have read that back then too. But those were all very old hoses...
By the way, I disconnected the handbrake and disabled the ESP, but that didn't help.

What about the topic of grinding? Has anyone ever checked this after a new build?

Hello,
Are you sure everything is going to be okay? Blocks, bolts, handbrake lever on the saddle?
Best regards, Dago.

Hi!

In my opinion, everything is free. The handbrake is disengaged.
The next step is to replace the brake hose and the brake caliper bracket, including the guide bolts.

Regards,
Brezelmann.

Hi!

Today I replaced the last parts. That is to say:

New brake discs.
New brake pads.
Brake calipers, new.
Brake caliper bracket (left side only), new.
Brake hose (left side only), new.

The brake is still getting hot.

That leaves me with only the hydraulic unit.
I'm registering the vehicle at the workshop now.

Question:
1. What is the cost of replacing the ESP (Electronic Stability Program) module?
2. Can VW check tire pressure?

Hello.
You probably won't achieve anything with that either.
The pistons in the disc brake, along with the brake pads, are pushed back (away from the disc) by two factors: any remaining imperfections on the disc surface and the tension in the seal lips. If you have properly released and adjusted the handbrake (???), I would recommend bedding in the rear brake pads, or even sanding them down beforehand. Both are used to create more tension on the cuff lips.
I would initially ignore any warm sensations in the groin area.
hg
Herbert.

Hello Herbert,

The handbrake is stuck.
The glass gets so hot that saliva immediately sizzles. A slight bluish tint is visible. Something is definitely wrong.

Regards,
Brezelmann.

Hello!

I've been out of the profession for a few years now.
Okay, I'll just write down what I'm thinking.

Normally, it's not expected for the brakes to get that hot.

When installing rear disc brakes, you first assemble the brake itself, then you pump the brake pedal to apply pressure and ensure the brake pads are properly seated, and finally, you attach the handbrake lever and cables.
You probably already know this, and you may have done something similar yourself.

I would do the following in that case:
Lift the car so that the wheels can rotate freely.
If you push the wheel with your hand, it should continue to rotate on its own for at least 5 revolutions; if it does, then it's okay. So, rear-wheel drive, and of course, without all-wheel drive.

If the wheels spin freely, take it for a test drive, and then try it again immediately afterward.

If the wheels are difficult to turn, the brakes are likely dragging.
I would briefly open the bleed valves to see if there is any pressure.
And whether the wheels will be free to move afterwards.

When I was an apprentice in East Germany, at the Trabant workshop, the first thing we would often do was adjust the play between the brake pedal and the master cylinder; it was adjustable, and that was a common problem. I'm not sure if that works with this particular car, but I think it might.

Otherwise, I just remembered something else.
but only theoretically, because I've never experienced it myself, but I once witnessed it during a training course:
The engine draws air out of the brake booster, and air needs to be replenished there.
It should happen from the footwell of the vehicle, and there needs to be a small filter, such as a non-woven fabric, mat, or foam, to prevent too much dirt from entering the brake booster.
People have said that when unusual problems occur with the brakes on older cars...
We should also keep in mind that the filters can become clogged or moldy.

Does the rear axle have a brake force limiter?
hg
Herbert.

Containers overflowing?

Okay...dear friends of braking technology , here is the solution.

After almost suspecting the ESP, I opened the bleed screw again today after braking. If it had been a backflow, the pressure could have escaped. But there was nothing. The brake was sticking.

So, I got another new brake caliper from the same manufacturer, installed it, and after the first bleeding, everything is fine, and the brake remains completely cool. Tomorrow, I'll bleed it again thoroughly and return the old "new" one. The manufacturer or reconditioner is FTE. It's incredibly frustrating to have wasted time and money because a brake manufacturer (!) can't manage its processes.

I would like to thank everyone involved here .

Quote:

So, I got another new brake caliper from the same manufacturer, installed it, and after the first bleeding, everything is fine, and the brake remains completely cold. Tomorrow, I will bleed it again thoroughly and return the old "new" one. The manufacturer or reconditioner is FTE...

Um (ahem...), why did you even install new brake calipers, and why not original ones? God immediately punishes small sins.
hg
Herbert.

Because it should be a repair that reflects the current value of the item.