2000 SLS Brakes Sticking. Any ideas?

[Brandon Meats]

Last week I was driving to work and I smelled brakes. Pulled in and noticed the LF brakes smoking! I know sometimes the hoses will pinch and not allow the brakes to release, so I changed the hose. Car drove fine for a few days, then it started doing it again. I saw the boot around the piston was torn, so I though maybe the caliper was hanging up. I proceeded to install both new front brake calipers and hoses (the rear brakes are just peachy). There was extensive damage done to the LF pads and rotors (which I just replaced about 3 months ago) so I resurfaced the rotors on a brake lathe and bought new pads, again. While I was in there I replaced the CV axle due to a torn boot and replaced the LF wheel bearing because I could hear a hum from it on the highway. The ABS light was on so I thought maybe the sensor in it was bad. Just finished up the job this morning and took the car out for a quick spin. It still seems like the brakes are sticking slightly because my MPG INST is showing about a 35%-50% reduction in mileage! I shift the car into neutral and it coasts, but the speed drops steadily. While in gear, the engine seems like it's working harder to keep momentum. I only drove about 2 miles and parked the car. I'm not gonna risk compromising all the work I just did.

The ABS light has been on since about the first of the year. I assumed it was the humming wheel bearing. I took it to the local dealer (O'Malley Cadillac) and paid $100 for them to tell me the ABS module was bad and a new one was $1000 + labor. The brakes were working fine so I opted out. They told me that the ABS module "lost communication" with the car and they couldn't even read the ABS codes. I recently purchased an ABS module from another forum member who is parting out a 2000 STS (I have a 2000 SLS so I'm assuming it should be the same module) I haven't put it in yet just due to the fact it looks like it's gonna be a chore (I do intend on replacing it though). Could the module be acting up and not allowing the brakes to release? Could there be a problem with the master cyclinder? Am I looking at it from the wrong angle?

Just curious if any of you other Caddy enthusiasts out there have come across or had a similar problem that you or had repaired. Any help, advice, or insight would be greatly appreciated.

[tateos]

Yeah - I think you;re on the right track - I think only the module and the master cylinder are left to replace

[submariner409]

Somewhere in the mix with the EBCM and ABS system is a proportioning valve - a widget that sends different hydraulic pressures to the front and rear brakes to prevent rear brake "overbraking". Don't leave that out of your troubleshooting.

[Brandon Meats]

I forgot to mention that ONLY the left front brake is acting up. I just replaced everything in the front brakes on both sides due to the fact I'm overly anal, and that my theory is that when one goes, the other isn't too far behind. A buddy of mine told me to try and get it to act up, then crack the line fitting on the module for the LF brake. He said if it releases the wheel, then the module is probably bad. I'd to it at the master cyclinder, but usually that's a front /rear split, so in theory both front brakes would be acting up. Two lines from the master to the ABS, then one line out to each wheel. I've got the module 'cause I was told it was bad. I might as well just change it. Anything weird I need to know about changing that? I'm sure that's gonna be a bi*ch to bleed. When the guy pulled it out of the car he just cut the lines and the wire harness. That way the lines are pinched and no dirt can get in. I sprayed some PB on them and they all cracked loose. Hopefully this module is good and then I can take it to the shop I used to work at and see if the computer will then communicate with it once it's in the car.