Happy Thanksgiving, I replaced the front brake pads on my 04 a6 s line, pushed the caliper pistons in with a c clamb like I have done dozens of times on other vehicles, I had the had the brake fluid resevoir cap off to let the brake fluid drain out , I refilled the resevoir and have mushy brake pedal, I have blead the fron brakes and still have mushy brake pedal, I am at my wits end. What could possibly cause the brake pedal to go mushy , I didn't open the system Any ideas?

 

Any Ideas anyone?????????

It acts like the MC is bad but it was fine before replacing the brake pads????????????????

I have bleed the rears and the fronts I dont have any idea what else to do?

 

Is the brake pedal spongy with the engine running too? Did you try driving the car and see how it stops? I have ran across them feeling a little spongy but after the car was running it stopped just fine.

 

Yes I have driven the vehicle , it will stop but the brakes stay mushy , you have to pump the pedal.

I read elswere that you have to hook a brake scan tool up to the vehicle to properly bleed it, this will open some valves in the abs unit. Something to do with the stabilty control system. Does anyone know anything about this ???????????????? I still dont under stand how air could have got into the system all I did was push the caliper pistons in.

Frustration

 

Take a deep breath, it's okay! Your brakes will feel spongy for a while after replacement. It doesnt hurt to go out and really break them in. Going 40-50mph and slamming the brakes. They just need to be broken in. Its normal.

 

Johnny A4 I appreciate the positive outlook but I have done dozens of brake jobs before and Managed a autocare center for 5 years believe me when I say its not brake pad wear in thats the problem. New brake pads dont cause the brake pedal to go the the floor. There was either contaminated fluid in the calipers that was pushed back into the system or there is air trapped in the anitlock/stability control module.

 

Have you ever replaced the brake fluid? This is part of the maintenance routine that needs to be performed every 2- years, depending on manufacturers. Brake fluid absorbs moisture and become inefficient. Also the excess moisture will begin corroding the calipers.
This may not solve your problem (the issue may be elsewhere such as the ABS pump, etc...) but fluid replacement needs to be done no matter what so I would start there.

 

Here's the deal... First of all let me credit my opinion by saying I was a certified audi technician for two years and have done more than dozens of brake jobs on audi's. That said, you have no problem with your brakes. Relax, it IS normal for your brakes to feel that way after a brake change. You will notice it will get stiffer the more milage you put on your car. Your inquiry is a typical customer complaint I and thousands of other audi Techs and service writers have dealt with over and over. Audi is a different animal from other brake system you may have replaced brakes on before. Call an audi dealer and they will tell you the same. I was an audi tech and have moved up in the dealership and we have the top techs in the nation who will agree with me. The new pads need to be seated with the old rotors, the two surfaces haven't "mated" yet which is causing your issue. Audi also recommends to do several "light to moderate" stops following the replacement. Hopefully this helps. I personally remember my first pad replacement on an audi and can remember I thought I F'd something up. My mentor at that time laughed at me and told me all I 've told you

 

Here is the deal Johnnya4 , I respect your opinion but the pedal will go to the floor , you can pump it up standing still and it will get harder then loose its pressure and return to the floor. This is standing still and has nothing to do with the two surface's matching as they are not moving against each other. Its just the ceramic pad pushing against a metal rotor , this contact can not cause the lose of hydraulic pressure on the pedal or in the brake system. You can not contribute this to brake pad wear in. Its not just a little soft it doesnt hold pressure. You obviously know way more about audi's than I do but if you could feel this I gaurentee you would not atribute it to pad wear in.

I have friend who is a tech at a import car repair shop (not dealer) who does a few audi brake jobs a week and he said he has never had this problem. The system is not loosing fluid , I cant get visable air when bleeding , so either the master cylinder just "went bad" at the same time I replace brakes or I have contaminated fluid as stated by previous poster or there is air in the abs controler that I cant get our with out a brake scan tool.

Johnnya4 assume its not brake pad wear in , what would be your next move?????

I apreciate your input

Jesse

 

voight24, I think you need to go a VW/Audi shop. You have
air in the ABS system, which is up high. A power bleed will
fix the problem.