Question about 2004 Audi A6

3 Answers

Problem occurs with Audi S6 MY2001 brakes. Brake rotors and pads are replaced (new, original). Brake pedal is sinking down when when motor is running. Bleeding is done many times under preasure and without. Master cylinder is replaced with new one. Problem remains.

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  • Andrius
    Andrius Nov 09, 2010

    When engine is off, yes pedal is hard. At first I replaced original size cylinder 24,5mm. Problem persisted. Second step - master brake cylinder from more powerful models like RS6 with diameter 26,99mm. After this replacement problem was solved for a week. Now pedal is sinking again, and brakes are worse than before.

  • Andrius
    Andrius Nov 09, 2010

    Hi azraelsrl, thanks for another idea. Actualy I did not mentioned but with a first master cylinder replacement we used DOT4, second time, when RS6 cylinder was installed it was DOT5.1 Both times it was Comma brand product. Anyway, tomorrow I'll try to check vacum system as your collegue advised.



    Regards, Andrius

  • Andrius
    Andrius Nov 09, 2010

    Hi fordexpert, I will try to test vacuum system tomorrow. I also wanted to blame ABS unit for this problem. There can be a possibility that one of soleinod valves is not closed, but if ABS unit is unpluged (I mean electricaly) when engine is runnig problem stil remains. Anyway I will keep you informed on results. Regards, Andrius

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Hi! Only one thing can cause this... A faulty HYDROVAC. If it's faulty you'll have vacuum leak which can cause the brake pedal goes to the floor when you step on it. This is dangerous for the brakes won't be consistent. Have it replaced and you'll be good. Hope this helps and thank you for using FIxYa!

Posted on Nov 10, 2010

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  • Audi Master
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This sounds like a Vacuum boost problem. You can test for this several ways and the problem can also be (IF equipped with) a Vacuum Reservoir. You can use a spray can of Brake cleaner if it is safe for rubber and plastic parts. Spray around the Vacuum Booster and the Supply hose from the engine while it is running. Then spray the Vacuum Reservoir. A change in RPM will indicate a leak.

You may have to use to have a foot on the Brake pedal while you perform this test.

You can also use a simple Vacuum gauge on the engine and watch if the Vacuum level drops while the Brakes are applied.

As far as the Hydraulics go, if you have the equipment you can put a "T" fitting off the Primary plumbing on the Master cylinder and see if the problem is in the front or rear Brake line. I am not familiar enough with Audi products to know if the ABS unit can leak internally, but the bad valving that you thought was occurring in the Master cylinder may actually be occurring in the ABS unit.

You can gauge and test pressures in and out of the ABS unit, but at a point the testing costs more than a new part. Would like to know the outcome of this. I hope to have given you some new ideas on solving your problem.

Posted on Nov 09, 2010

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Simple test: press on the brake pedal with the engine off. If it's rock hard and sinks very little then the braking system is in perfect functioning order. In that case the servo for the brake is too powerful and takes away all the effort: you will have to verify it, maybe it was replaced with the wrong unit - a smaller, weaker one should have been used.

Posted on Nov 09, 2010

  • Azrael SRL Nov 09, 2010

    In that case you must do another test: replace the brake fluid with another brand and bleed the circuit thoroughly. If the problem is fixed but it returns it means that a brake is partially seized, overheats, and the braking fluid boils. Check their temperature.

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1 Answer

I have no brakes


It can be issue with master cylinder or the problem is there is still some air there in the system that has to be bleed. Or else the parts replaced are not aligned properly/.I suggest everything back.


There are few help links mentioned below to troubleshoot the issue.


Click the link below and follow its procedure: -----


All types of brake problems and repairs

http://howtobyme.blogspot.com/2011/11/abs-and-service-light-comes-on.html

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Brake Fade Issue?

http://whoisbyme.blogspot.in/2012/07/brake-fade-issue.html

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Brake System Troubleshooting?

http://technoanswers.blogspot.com/2011/11/brake-system-troubleshooting.html

----------

Car Brake lines have no pressure?

http://schematicsdiagram.blogspot.com/2011/12/car-brake-lines-have-no-pressure.html

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Car Brakes Dragging?

http://repairhelpcenter.blogspot.com/2011/12/car-brakes-dragging.html

-------------

Car Brakes grabbing?

http://repairhelpcenter.blogspot.com/2011/12/car-brakes-grabbing.html

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Car Brakes Making Noise?

http://repairhelpcenter.blogspot.com/2011/12/car-brakes-making-noise.html

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Car Brakes Pulling?

http://repairhelpcenter.blogspot.com/2011/12/car-brakes-pulling.html

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Pulsating Brake Pedal?

http://repairhelpcenter.blogspot.com/2011/12/pulsating-brake-pedal.html

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Spongy brake pedal?

http://repairhelpcenter.blogspot.com/2011/12/spongy-brake-pedal.html

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Hard Brake Pedal?

http://repairhelpcenter.blogspot.com/2011/12/hard-brake-pedal.html

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Fading Sinking Brake pedal?

http://whoisbyme.blogspot.in/2012/06/fading-sinking-brake-pedal.html

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Feels Like Brake pedal Pulsating

http://repairhelpcenter.blogspot.in/2012/06/feels-like-brake-pedal-pulsating.html

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What is Brake Drum Bar?

http://repairhelpcenter.blogspot.in/2012/02/what-is-brake-drum-bar.html

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ABS light stays on but brakes work fine?

http://howtobyme.blogspot.com/2011/11/abs-light-stays-on-but-brakes-work-fine.html

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Vibrations while braking On Chevrolet Van?

http://technoanswers.blogspot.in/2012/04/vibrations-while-braking-on-chevrolet.html

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Dragging brakes?

http://howtobyme.blogspot.in/2012/03/dragging-brakes.html

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Brake pedal stuck?

http://howtobyme.blogspot.in/2012/03/brake-pedal-stuck.html

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After replacing brake rotors and pads, brake pedal remains on floor?

http://technoanswers.blogspot.in/2012/02/after-replacing-brake-rotors-and-pads.html

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How to replace Brake Power Booster?

http://repairhelpcenter.blogspot.in/2012/02/how-to-replace-brake-power-booster.html

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1997 Chevy Tahoe Brake lights not working?

http://technoanswers.blogspot.in/2012/02/1997-chevy-tahoe-brake-lights-not.html

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How to service Drum brakes?

http://repairhelpcenter.blogspot.in/2012/02/how-to-service-drum-brakes.html

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What type of problems usually noticed on Drum brakes?

http://repairhelpcenter.blogspot.in/2012/02/what-type-of-problems-usually-noticed.html

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How to test Drum Brakes?

http://repairhelpcenter.blogspot.in/2012/02/how-to-test-drum-brakes.html

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Brake Bleeder Screw Function?

http://repairhelpcenter.blogspot.in/2012/02/brake-bleeder-screw-function.html

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Toyota Tundra: Parts diagram to replace Brake Drums?

http://technoanswers.blogspot.in/2012/06/toyota-tundra-parts-diagram-to-replace.html

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Squeak and grinding sound is heard when brakes are applied?

http://technoanswers.blogspot.in/2012/02/squeak-and-grinding-sound-is-heard-when.html

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Brake Pads Inspection on Acura Integra?

http://repairhelpcenter.blogspot.in/2011/11/brake-pads-inspection-on-acura-integra.html

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How to remove Brake Pads on Acura Integra?

http://repairhelpcenter.blogspot.in/2011/11/how-to-remove-brake-pads-on-acura.html

--------------

How to remove Brake Disc Rotor on Acura Integra?

http://repairhelpcenter.blogspot.in/2011/11/how-to-remove-brake-disc-rotor-on-acura.html

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Brake Caliper OVERHAUL on Acura Integra?

http://repairhelpcenter.blogspot.in/2011/11/brake-caliper-overhaul-on-acura-integra.html

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How to remove Brake Caliper on Acura Integra?

http://repairhelpcenter.blogspot.in/2011/11/how-to-remove-brake-caliper-on-acura.html

------------

How to remove Parking Brake shoes on Acura Integra?

http://repairhelpcenter.blogspot.in/2011/11/how-to-remove-parking-brake-shoes-on.html

-----------

How to remove Parking Brake Cable on Acura Integra?

http://repairhelpcenter.blogspot.in/2011/11/how-to-remove-parking-brake-cable-on.html

-------------

Brake pedal is pulsating and vibrating?

http://repairhelpcenter.blogspot.com/2012/01/brake-pedal-is-pulsating-and-vibrating.html

----------

2002 Ford Windstar: Brake Warning Light ON dash?

http://schematicsdiagram.blogspot.in/2012/06/2002-ford-windstar-brake-warning-light.html

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These details will help.

Thanks.

Dec 09, 2012 | Cars & Trucks

3 Answers

WHy dose my brake pedal push back and make a grinding noise


Look through the openings in your front wheels and look at the front rotors-are they gouged up? You are probably running metal-to-metal, pads to rotors.
Chances are real good your rotors will have to be replaced along with new pads, but if you catch it early enough you might be able to have them machined, although nowadays that is hardly easy to get done and the savings usually is not as significant as it once was.

May 23, 2011 | 1995 Pontiac Bonneville

2 Answers

Brakes sink to the floor


by stating that your pedal sinks to the floor, you leave 3 options open 1.) the master cylinder seal is bypassing allowing the fluid to bleed by the proper correction is to rebuild the master cylinder.
2. One of your drum brakes has a wheel cylinder that has failed causing a noticable behind the tire leak (most common) correction is to replace all brake hardware and wheel cylinder.
3. One of the brake lines is cracked,broken, inspect for leaks and replace with new line.
4. notice on disc brakes if a brake caliper fails (part that squeezes brake pads to rotor) you will have the same symptoms of a broken wheel cylinder, this would of gradually occured feeling a heavy pedal or pulsation.

Feb 19, 2011 | 1994 Toyota 4Runner

1 Answer

How can I change the rotors and brakes on a 2006 Cadillac?


Front brake
Step 1: Identify Front Disc Brake Components
brake_pads_rotor.jpg
Front Wheel Drive Brake Assembly
Most front disc brake components include: brake rotor, brake pads, brake caliper, caliper mount and brake flex hose. Brake service usual occurs between 20,000 and 40,000 miles depending on driver habits, road conditions and brake pad/ rotor materials used.
Step 2: Remove Brake Caliper to Replace Pads
brake_pad_set.jpg
Removing Brake Caliper Mounting Bolts
Locate primary caliper mounting bolts; apply wrench pressure counter-clockwise (When looking at the head of the bolt) to remove the bolts, upper and lower. Make sure the bolt threads are in good shape and replace if necessary.
Step 3: Remove Front Brake Caliper
remove_brake_caliper.jpg
Remove Front Brake Caliper
After removing the primary caliper mounting bolts lift the brake caliper off of the rotor and then tie or secure to the side, being careful not to bend or kink the brake caliper flex hose. Thoroughly inspect brake caliper and brake hoses for leakage, cracks or chaffing and replace as needed. Next remove the brake pads (If not mounted in the caliper) and secondary caliper mounting bolts. Notice how great protective gloves work, most technicians use them on the job today.
Step 4: Remove Brake Pads
remove_brake_pads.jpg
Remove Front Brake Pads
Once the brake pads have been removed, make sure if there is anti rattle hardware to transfer to the new brake pads. Some brake pad manufacturers will include the proper lube (Caliper slides) and anti-rattle hardware to ensure proper performance of their product.
Step 5: Remove Caliper Mount
remove_brake_pads_holder.jpg
Remove Caliper Mount Bracket
Finish removing secondary caliper mount bolts and remove caliper mount. Note: clean and lube caliper slides and pad friction surfaces of all foreign material or build-up.
Step 6: Remove Brake Rotor
brake_rotor.jpg
Remove Brake Rotor
With the caliper mount out of the way you can now remove the brake rotor. Sometimes it can get stuck so you may need to tap it with a hammer or use penetrating oil to free it up. Some manufacturers use small screws to hold the rotor on as well. Clean and inspect wheel studs, replace if any are damaged. Also clean bearing hub rotor mount surface to ensure the proper mounting of the new brake rotor. Inspect the ABS sensor wheel for cracks or damage and replace as needed.
Step 7: Depressing the Brake Caliper
compress_caliper.jpg
Resetting Brake Caliper
To install the new brake pads you must retract the brake caliper piston. Remove the master cylinder lid or open the brake caliper bleeder screw to allow excess brake fluid to be released if necessary. Install C clamp tool and gently tighten clamp until caliper piston is fully depressed. Note: use old brake pad to protect the caliper piston. Close the bleeders once the piston is retracted completely
Step 8: Installing New Brake Rotor
new_brake_rotor.jpg
Install Brake Rotor
Install new brake rotor, the new rotor is manufactured with a protective film over the rotor to keep it from rusting, remove protective film with brake cleaner before installing; also after the brake job is complete you may experience a small amount of smoke from the rotor when first used. This is normal and will go away after the first couple of uses.
Step 9: Installing New Front Brake Pads
new_brake_pads.jpg
Installing New Brake Pads
Reinstall the front brake caliper mount, and then install front brake pads. Make sure the pads are seated properly in the caliper mount; it must be a close fit to work properly..
Step 10: Reinstall Front Brake Caliper
front_brake_rotor_pads.jpg
Re-Install front Bake Caliper
Reinstall front brake caliper and reinstall caliper-mounting bolts, recheck all mounts and mounting bolts. Check the caliper slides to be sure there is no bind and that the caliper moves freely back and forth on the caliper slides. Bleed brake system per manufacturer's specifications to relieve any air trapped in the system. Before driving the vehicle, push the brake pedal down and let it up slowly, repeat until normal brake pedal operation resumes, this operation is forcing the brake pads to travel to the brake rotors.

Dec 18, 2010 | 2006 Cadillac STS

1 Answer

Brake pad replacement 2004 audi a4 and rotor how do i do and what tools are neccessary?


YOU NEED REMOVE A LITTLE BRAKE FLUID FROM MASTER CYLINDER.THEN YOU RAISE VECHICLE SAFELY.SUPPORT IT WITH JACK STAND.MAKE SURE VECHICLE IS ON LEVEL SOLID GROUND.REMOVE TIRE OR WHEEL.THEN YOU NEED A LARGE C - CLAMP.PLACE C - CLAMP OVER BRAKE CALIPER AND BRAKE SHOE BACKING.TIGHTEN C - CLAMP JUST ENOUGH PUSH CALIPER PISTON BACK IN CYLINDER BORE TO REMOVE CALIPERS FROM ROTORS.TO REMOVE BRAKE CALIPER YOU NEED 2 OPEN AND BOX END WRENCHES ONE TO HOLD CALIPER SLIDE PINS AND THE OTHER WRENCH FOR LOOSEN CALIPER BOLTS.THEN YOU REMOVE CALIPER AND REPLACE FRONT BRAKE SHOES.IF YOU NEED TO REMOVE BRAKE ROTORS JUST REMOVE THE BRAKE CALIPER CARRIER SUPPORT BOLTS THE REMOVE THE BRAKE CALIPER CARRIER SUPPORT THEN REMOVE ROTOR.YOU NEED TO REPLACE BOLTS WITH NEWS AND USE LOCK TIGHT.THEN YOU PUT IN NEW BRAKE PADS IN CALIPER PUT CALIPER BACK ON SUPPORT CARRIER.REPLACE WITH NEW BOLTS USE LOCK TIGHT THEN TORQUE BOLTS TO 26 FT LBS.MAKE SURE MASTER CYLINDER COVER IN PLACE.WHEN YOU FINISH REPLACING BOTH FRONT BRAKE PADS PUMP BRAKE PEDAL TO SEAT BRAKE SHOES AGAINST BRAKE ROTORS SO YOU WILL HAVE FIRM BRAKES WHEN YOU APPLY THEM. THEN CHECK YOUR BRAKE FLUID LEVEL IN MASTER CYLINDER MAKE SURE ITS NOT LOW. MAKE SURE YOU HAVE FIRM BRAKES BEFORE DRIVING.IF YOU HAVE ANY PROBLEMS CHANGING FRONT BRAKE PADS YOU CAN GO TO ANY AUTO PARTS STORE AND BUY A HAYNES REPAIR MANUAL.

Jun 16, 2010 | 2004 Audi A4

1 Answer

Spongy brakes


So long as the brake booster is working, test it by turning on the engine, press the brake pedal all the way down, then shut off engine keeping your foot on the brake pedal, if the pedal comes up slightly pushing against your foot then the booster IS working.

Did you BLEED the brakes??????

Mar 29, 2010 | Chevrolet Suburban 1500 Cars & Trucks

2 Answers

I just bought my 2004 buick lesabre and I already need new brake pads. I dont know whether I should get med grade pads or (high grade)ceramic pads. If I get the high grade would I special rotors?


You can use your stock rotors with ceramic pads. If you feel that the pads wore down too quickly then they may have been a less than optimal type. Keeping disc brakes clean is key to making them last longer. When there is brake dust and naturally occurring rust built up in the calipers and slides, then they don't release immediately or completely when you let off the brake pedal and they may actually drag your pads.

Mar 16, 2010 | 2004 Buick LeSabre

1 Answer

Brake pedal judder on 1996 audi a4 when slowing


Have the rotors turned or the discs cut means the same thing either way but yes your disc.

Dec 02, 2009 | 1996 Audi A4

2 Answers

Brakes are terrible.


Sounds like two issue. The ABS unit might need replacement (known issue for ABS lights on) and the brakes need to be quality parts (ATE, Brembo, Girling, etc.) , not discount auto or pep boy type brakes. Those don't stop well. If the pedal travel is excessive, bleed the brake system first. If its still excessive, its most likely the master cylinder, not the booster (booster will make the pedal hard).

Mar 16, 2009 | 1998 Audi A6

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