Hey youall my name is Danny. I have a 2000 Audi A4 quattro 1.8t tip. My audi has run into a problem. About a month ago ( December 2008) I replaced my rear brake pads and rotors at about 82,000 miles. I compressed the caliper with a rental tool ( everdrive tool at oreilly AP) everything good, I replaced the brake pads and rotors, i bled the brake lines, cool. A month later (january 2009) the brake light started flashing on my gauge panel ( this is the light that signifies the hand brake is on) but i did not know what it meant was running fine. A week ago from ( jan 20 the brake pedal got soft on me ( this got me worried). Then yesterday coming home from work the brakes started dragging and I drove home at under 30 mph. Today, I took my car to a shop and put it up on the lift. I tracked the dragging wheel to the rear left side. I have a chiltons repair manual dived in and saw a note that says that the praking brake cable must be adjusted when the rear brake pads are replaced. so me and the the mechanic ( Tony) at Kar kare moved the adjustment. With no adjustment left to give the parking brake released of the braking pressure. We that was it then test drove it and pulled the handbrake then again the same wheel began dragging with handbrake down and no brake pedel pressure. So we removed the wheel again removed the parking brake cable to isolate the problem. Removed the caliper and compressed it again to investigate and reset the brake pads. We placed the caliper back on and pressed the brake and it began to drag again. I took it for a test drive with no use of the hand brake this time and it seemed fine with little brake pedel pressure but when i pushed down on the pedel harder, the brake really got stuck and i turned around back to Kar Kare. We removed the wheel and opened the bleeder screw and the caliper realeased so (Tony) told me it was then the blake line that is bad. THis sound kinda weird for being a 2000 but tommorow i am gonna flush the whole brake system with new fluid and try again.

Can youall help please,
Danny

 

If the brake peddle is going soft I would try bleeding the brakes again you may have gotten some air bubbles in the line.

 

I remember reading when I first joined the forum that it is a common problem for the calipers, especially in the rear, to get stuck, typically from the parking brake. Last I heard there is no rebuild kit for the rear due to the parking brake system, so most people end up replacing the entire caliper. PureMS has the rear caliper available. Just my two cents. Search the forum, this topic has been addresses quite a bit. Good luck!

 

Quick question. When you originally did your brakes, and compressed the caliper piston, did you take the cap off the master cylinder ?

 

While you are replacing parts down there you should also replace the stock lines with steel braided ones. I would do all 4 if I were in your shoes.

 

I did not remove the master cylinder resavoir cap when i compressed the calipers. I did notice brake fluid leaking out of the resevoir on the top vent sorta deal where there is like a flathead plug on top of the resevoir. I have been thinking that that has been related to my problem.

Update: I changed the dragging rear left caliper work fine for about half a day, then all four wheel calipers began dragging. I stopped my A4 on the side of the road and felt all wheels hot from the brakes holding. The car is parked now im thinking about replacing the master cylinder.

 

So do you think the resevoir could be busted from not removing the cap during caliper compression?

 

If you did not remove the cap prior to compressing the caliper piston, then you have air in the system. You will need to bleed the all calipers. You will need to start at the passenger side rear caliper, then the driver side rear caliper, then the passenger side front caliper, and lastly, the driver side caliper. It is important to start at the furthest caliper from the master cylinder. The whole system needs to be bled. Its not too difficult, if you have someone helping. Do you know how to perform this?

 

I have tracked the problem down to my ABS controle module. The calipers have pressure but when the lines from the module are released the calipers loosen up. I did some research and found out that other Audi A4 owners have had the same problem around 80,000 miles. One mentioned a company online that rebuilds these modules at modulemaster.com and the claim is that the problem is known in the wiring from the bosch ABS modules and can be fixed better than new, all for around $300 bucks compared to the dealers $1700 price on a new unit. Ouch. So i looked up the site and attempted to contact them but got no response through email or phone. I called and the number is still active for Moudule master business but no answer. I wanted to know if youall have heard of this company and its potential or is this company dead?