GMikes97A8Q

I have a 97 A8Q with around 86,000 miles. I am in the process of maintaining the brakes. I have purchased new brake pads and new rotors all around. All installed by my machanic, along with new brake fluid. I thought everything was ok until last friday. I saw alot of smoke coming from my rear brake pads. It smelled very bad also. Took it back to the mechanic on Monday (today). He said the emergency brake was stuck (engaged) and would not release. Further, he quoted over $1000 to fix. Including new calipers, pads and rear rotors (again). Not sure what to do at this point. I'm a bit frustrated. Anybody have any suggestions? I'm currently looking for a source for new rear calipers. Mechanic thinks this is where brake cable is bound up and won't release.

PaulW

If the cables are stuck, then replace the cables. Doesn't cost $1,000 to do that. If it's the caliper, it's only going to be one side that's not releasing, you don't need to replace the pads and rotor, just the caliper. Sometimes the piston boot rips and it rusts inside and causes it to stick.

Check out the rear wheels, did one have brake dust on it and the other doesn't? That's the one with the stuck caliper or brake problem.

When you do the back brakes, the pistons must be screwed back into the calipers, with a tool, or just with a pair of channel locks on the pistons and a C clamp on the piston, providing pressure to get it back in. Once it's all in, the emergency brake is self adjusting, just pull it a few times and it works correctly.

I imagine if this just started after a rear brake job was done, it has something to do with the mechanics job, not something that popped up that was never there before.

pw

PaulW

...parking brake mechanisim that is sticking. I bet it's not properly adjusted. You need to pull the parking brake after you do the brake job a bunch of times to adjust the parking brake. Did that get done? Did you try it since then?

Sometimes during repair the spring can get out of wack and it needs to be manually reset (as when putting in a new caliper). I'm talking about the spring that works the thing. It can cause the caliper to stick. But I doubt that's it.

Maybe somehow it's grabbing your brake rotor for some reason and not letting go. I had that happen on my 91 200q, but that was from road salt on the piston (the boot was ripped for over a year) and it would stick. The brake wouldn't loosen up until the pad wore down. You could see which wheel it was by the amount of brake dust. If you used OEM pads, it will be evident. Your available acceleration will also be vastly reduced.

Have your mechanic look into the parking brake assembly. If you need technical references, tell me and I'll help you out.

It is important that you troubleshoot it down to the wheel, most likely it's not both. Components of the system - handle in car, cables, spring assemblies on caliper, calipers and pads. I highly doubt it is the pad, and it sure has nothing to do with the rotors! Nor will they have to be replaced if new.

pw

GMikes97A8Q

Your a good man Paul. Thanks for all the good ideas. The e-brake needed to be adjusted from before the brake job. I asked them to do it after the brake job but they said they would have to remove alot of components from the rear end to get to it (quote was $350) to adjust e-brake. I said not thanks.

Right now the e-brake is basically disconnected. I will print out some of your e-mails and see if I can trace through it. Also, the rear driver side rotor appears to be moving freely now. no more overheating at this point. The rotors on both sides appear to be scaped up a little bit and I am getting a little bit of a shimmy when braking.

PaulW

I don't understand why the emergency brake needed adjusting before the brake job. It has a rachet assembly to adjust for the piston traveling out due to brake pad wear.

If you have shimmy when braking, then I would look at the front brakes. You said you had them replaced with the rotors. Did you use OEM parts?

A couple of things:

If the rotors were replaced and the hubs not cleaned, they might have foreign material or rust on them causing rotor shimmy (runout) in the front. Corrective action is to remove the rotors, clean, and reinstall. Ensure rotors are seated before torquing wheel bolts down. Use a torque wrench on bolts to ensure even pressures.

Make sure the brakes are broken in. That entails slow to moderate stops only for the first 20-30 miles. After they get seated, then you can increase brake pressure. If they at have least a couple hundred miles on them, you can always try sucsesful high speed stops.

It might take a couple of weeks or a couple thousand miles to true the rotors with the brake pads. It all depends on the starting runout of the rotors. If it is small, then it won't take that long to get smooth braking, but if it's high, it's going to take longer.

For your immediate problem, focus on the left rear caliper, that's probably where your problem is. It's not that hard to fix. The wheel is going to have to come off for an inspection of the emergency brake and cable assembly.

pw

GMikes97A8Q

The rotors and pads came from Blaufergnugen Audi, off the internet. I thought the e-brake needed adjustment because I have always had to pull way up on the handle, to the point that it lifted the arm rest. Even then the car would roll back until the transmission stopped the car. I bought the A8 abount 1 year ago with 75,000 miles on it, I now have around 86,500.