After getting out of the car the other day I could smell a burning smell coming from both the rear rotors. I could also feel heat radiating off both rear rotors. I went ahead and replaced rotors and pads and still the rear rotors were over heating. I took everything back apart again and cleaned out and re-lubed the caliper sliding pins and caliper on both sides. (The pins seemed to be sticking a little) After doing this, the drivers side rear seems to be working fine but the passenger side is still getting way to hot. It still seemed like the sliding pin were sticking some so I went ahead and put in a new caliper bracket and new pins. Needless to say, this did not help. I then took the car into the dealer to have them look at it and I was told that everything was ok and they could not find any problems with any braking components... Any ideas as to what could be causing this? Master Cylinder? Proportioning valve? Thanks in advanced for your feedback.

 

When was the break fluid changed?

 

Im not sure, I just purchased the car this October with 60K on it.

 

The caliper itself might be sticking. How many miles are on the car and what condition did the calipers appear to be in?

 

Highly doubt brake fluid.

Parking brake dragging?

 

get an infrared thermometer to measure temps cold and then after a drive.
if acura said all was well; i'd double check with the data you just collected with the infrared thermometer.

then try re-lubing the sliding pins, etc.

the above poster; might be on to something with the parking brake.

 

Bought the car in October with 60K and im just about to 65K now. Calipers seemed to be ok. There was a little rust. (I live in the Chicago area so lots of salt on the roads) Cleaned the caliper as best I could with a wire brush and re-greased it as well. Seems to be retracting fine also.

 

Parking brake seems to be ok as well. Ill check before and after temps today

 

did u check the parking brake? parking brake is like a drum brake inside your rotor in rear and it might be dragging, worth a look

 

Sub'd.

Mine was/is doing this binding you're speaking of. Sometimes it does, sometimes it doesn't. '05 TL, 6MT, 101K miles... It's shaving a couple mpg, and now the pads have been worn down to the noisemakers and my poor ride sounds horrible. I'm scheduling to upgrade to StopTech rotors and pads all around because they're rusty as hell and it's just time, but now you're scaring me it might not fix it. I'll be doing fluid and new lines as well, which I think was something you didn't mention. Thanks very much for posting and it's very curious that all the work you've done hasn't fixed it.

 

Ok. If the rubber seals looked good and it's retracting fine then the caliper is probably good.

You might try jacking up the car and spinning the rear wheels by hand. That might give you an indication of how much it's dragging and where. Like someone else said, it could possibly be the parking brake.

 

Chessie - My next was going to be to replace the brake line to that caliper. I have heard if there is damage inside the line (a kink) that the brake fluid can be pushed trough to the break fine but then has trouble releasing back through the kink keeping pressure built up on the caliper.

Splew - Rubber seals look oh and they seemed to be retracting just fine. When I jack the car up and spin the wheel there is some resistance. Sounds pretty uniform. The resistance is much less from when I first noticed the problem.

 

Mine did the same thing. Change your rear break fluid lines. They are only like $25 bucks. I bet one collapsed on the inside. That fixed the issue for me

 

There are two things that you can check. The caliper and the er brake doesn't open.

 

Make sure you have some clearance where the brake pedal lever contacts the push pin under the dash for the master cylinder when the pedal is in the relaxed position (at the top of it's travel). That small amount of clearance has to be there, if it's not there pressure will build up in the system. If thats ok change out that brake hose & bleed your brakes.

 

Normally, if a brake line is ruptured internally one can check when the condition occurs, remove the caliper and try and push the piston inward, if it doesn't move, open the bleeder and try again, piston should move in easily. Might be a little warm so be careful. Certainly infrequent that a brake line to give up, but two at once? It's possible that someone clamped the brake lines and destroyed the internal lining though.

 

If the parking brake was dragging he would have struggled to get the rotor off. Replace the caliper. I just had one yesterday same issue. One side would get super hot, but the caliper appeared ok. Replaced it and it was fine after that.

 

I think it might be the rear brake hoses. I had the car up on the lift yesterday and opened the bleeder and that "extra pressure" seemed to be released right away. The tires would spin with much less resistance than previously. Unfortunately I have to wait until Monday for them to come in. Ill let you all if this was the problem. Thanks for your input.

 

Did you by chance have the brake line twisted while putting the caliper back on???

 

This is what I was thinking. When I did this professionally for like 6 months lol I saw people using vice grips on the lines to avoid pushing fluid back through the system when retracting the piston. It definitely happens and at this place they supplied us with the line pinchers that were a lot more gentle on the lines not that I would even use those on my car.

This situation is looking like it might be a combo of a stuck pin a d a bad brake line but I would definitely replace both lines. Even if there's only a few psi trapped in there that's 6 psi of apply force if the piston area is 2" squared.

 

I Hate cars/3rd Gen - Just finished replacing both hoses and still expierencing the same problem. I was pretty careful with the hose while taking off the caliper but now both have been replaced and I am still having the same problem on both rear brakes. The Passenger side rear has a new caliper bracket and pins so I dont think that is problem. Any other ideas?? Could there be something wrong with the master cylinder? Or is there some kind of proportioning valve that could not be releasing pressure in the brakes?

 

Make certain that the caliper moves easily on the lubricated pins as you can try without the installation of the pads. Make certain the pads sit properly within the caliper, flat on the inside/outside.

 

Looks like the proportioning valve might be going bad or is gummed up with debris. Did a power flush on the brake fluid to try and get rid of any debris in the valve and changed brake fluid. Seems to be doing much better than before, temp and resistance on both rears are way down. I think Im going to drive it around another day or two and do one final flush and see what that does... Otherwise it looks like im replacing the proportioning valve.

 

It's not the prop valve. The rear brakes get full line pressure during normal easy stops. The prop valve is doing nothing until you get on the brakes hard and then it begins reducing pressure to the rears. It can't increase pressure, it can only reduce pressure.

 

Also, see if the drivers side front rotor is running hotter than the passenger side front.

 

I Hate Cars - Ill check that out today and get back to you. Is there anyway the prop valve is allowing the pressure to build up and not release? Generally, the temp is ok when I drive 20 min or less. It when I drive for 20min or more that they start getting really hot...

 

Find the smoking gun on this, OP?

 

Still have not found the problem... I have pretty much eliminated everything except for the master cylinder or the proportioning valve as the problem. Any ideas on how to tell if its the prop valve or the master cylinder?

 

I am having the same problem. I spoke to the service over at the dealer and he said it sounds like the brake pedal needs adjusted. He thinks the brake pedal is staying slightly pressed. He said abs system can also cause fluid not to release but he said more than likely a light would come on.

 

The abs could be a possibility, but I have no light on as well. I dont think it could be the brake pedal issue with mine because the overheating of my rear brakes is not consistent. Sometimes both rears will heat up. Other times it will just be the passenger side, sometimes it will only be the drivers side and occasionally both will not overheat what-so-ever. I'd hate to put in a new master cylinder or proportioning valve without knowing which, if any, is causing the problem.

 

I believe the proportion valve is part of the master cylinder on our cars. The service department said they highly doubt there is a problem with the master cylinder or prop valve. They thought i either had a nother bad hose or my brake pedal needed adjusted. I am going to adjust the rod on the pedal tonight and see what happens.

 

Good luck, let me know if you have any success. I already replaced both rear brake hoses without any luck too.

 

I am currently having similar problems. I had a leak in the brake M/C. Thought it was oil. It stopped leaking and my car was driving fine for a couple weeks. So I thought it was fine. Then my drivers side rear brake locked up. The piston had ceased. I replaced the caliper and lost pressure to the brake pedal. Then I finally noticed the brake Master Cylinder was leaking. So I replaced that as well and bled the lines all the way. My break pedal still drops to the floor. I have to pump the brakes to stop. Any suggestions?

 

when i installed my MC, i forgot to take off the old rod seal.
two seals dont make a better seal .
it introduced air into the system.
I ordered a new MC and while un-installing i found my mistake.

 

I definitely removed the old rod seal. After flushing, my car still doesn't have much pressure.

 

needs to be bled, then.

 

I bled it already. I completely bled the old fluid out until the new fluid was coming out on all four tires. Im thinking about bleeding them again one more time to see If it'll make a difference.

 

do you have the factory brembos?
there's a certain sequence that you bleed.

I bled at least 5 times.

 

I went in the exact order from what the Haynes manual said as well as online forums. why did you have to bleed them 5 times

 

^do you have brembos?

I bled at least 5 times, because there was MAJOR air in the system.