Alright - I'm baffled with my brakes. I just started getting a spongy brake pedal. One pump get's it back up stiff. I noticed my driver side rear rotor is rusty in the area where the brakes rub.

After driving the car, I felt the rotor, in which it wasn't warm at all. I then felt the passenger side - this side felt luke warm, but wasn't hot to the touch like the fronts (I'm not sure if that's how it's supposed to be).

I checked the fluid and noticed it was low. Went ahead and topped it off. No change, so I went ahead and bled the brakes (rear). I took her for a spin and still have the spongy feel with a one pump to get her back up. I checked the rotors in the rear again - The driver side was cool to the touch, but this time the passenger side was actually hot.

Can the rear caliper actually bleed internally causing a spongy feel? The calipers I'm used to are the front style you push in and the only way they can go bad is leaking. The brake hoses look alright as well.

Anyone experienced this, please share...

Thanks
Jim

 

I would first start by doing a full bleed of the system working the way around the car in the correct order. Could have a seized caliper if the rotor is hot after driving, a semi-common problem on these cars. Might need to replace them, but start with a full bleed and make sure all the air is out and all new fluid is in.

 

+1 and let me copy/paste something i've said in another thread.

I'd say take it to a shop that you trust. Have them check all calipers, then have them bleed all calipers and re-fill with fresh fluid. I dunno if there was something done to the car previously, but if someone was changing the calipers and didn't bleed 'em, the could of put some air in the system.

All i can tell ya man is that i had two sticking rear calipers which i asked my neighbor to change, but he didn't bleed them so there was air in the lines. As a result, my pedal sunk to teh floor B4 i could get some response from it.

Last weekend, i went to an actual shop, and brought some SS brake lines along so that they could put them in as well.
So they swapped out the lines after which they had to properly bleed the calipers (2 man job, pumping the brakes 'n stuff). They topped off the fluid 2times while doing that so most of my fluid is fresh too.

Anywhoo, after doing all that I GOTS THE BRAKING POWER BACK!!! The pedal was never this stiff/responsive and the car never braked with such confidence!! (not to mention ABS actually stops the can in a split second)

SO THE BOTTOM LINE IS: GO GET 'EM CHECKED/SERVICED (get some SS brake lines in the process, if you want)

 

Come to NY and I'll handle it for you!! Or you can jack the car up. have someone step on the brake and check for frozen calipers one by one. Sounds like one of your rears are frozen. Also sounds like you have air in your line. and as an FYI, you dont "top off" brake fluid. braking performance will be the same on a low resevoir as a full resevoir and brake fluid doesnt just evaporate that quickly. If your fluid is low, you either have a leak or the most common cause, your pistons are out because your pads are low.

 

Thanks for the info guys.

I'm thinking the rear caliper is frozen, but I thought a frozen caliper creates a hard pedal, not a spongy feel. That's where I'm baffled and was wondering if a rear caliper can actually leak internally.

I'll go ahead and bleed the whole system and see what happens. The fluid was pretty dark, and while I'm doing it, I'll have someone step on the brake and see if it's operating.

Thanks
Jim

 

You can't feel a frozen caliper.

Dave

 

Spongy feel is from air in the lines, frozen caliper doesnt have a feel. If in fact you also have a frozen caliper, you dont need to have it repaired if its frozen in the non braking position. I lucked out and when my rear brake froze, it did so in the closed position. Brakes still work fine, just not that wheel. When i go for inspection i'll have it changed, im just too busy to do it myself.

 

I don't agree with this at all. With a front brake not working the car will pull hard in one direction under hard braking, and that's really dangerous. Not to mention that the front brakes do 2/3 of the braking, so now your braking ability is reduced by a solid 33%. Again, extremely dangerous.

Generally speaking, if you need to fix something to pass inspection, I think it's downright stupid to wait until inspection to fix it. Everything on our state's inspection list is very important stuff.

Dave

 

Ye well my car does pull hard right while braking but you learn to compensate. Nothing on a state inspection is important, the only purpose of an inspection is to rape our tax payers of there hard earned money, even after paying 2.50 a gallon at the pump. Emmisions, brake light, headlights, tires, all that stuff is kinda important but not a safety hazard.

 

You make me want to take the bus.

cant see without headlights. if you brake in front of me with no brake lights i am probably going ot hit you. bad tires and you cant stop. and that isnt a safety hazard? Jesus.

 

YOU ARE RETARDED.

 

Thanks for listing the color of your car, I will make sure I stay clear of all gold maxima's with NY plates whereever I drive. I will also pass this info to my family and friends

 

Yes you can.

If the pins freeze and the piston still works the caliper is only pushing on one side of the rotor. Now as the pads ware a bit the stroke the piston takes becomes longer and longer, increasing your brake pedal stroke.

The rusty rear rotor is telling you something. Disassemble the rear brakes and inspect them. Make sure you check the pins, if they are frozen replace them.

 

You don't need to replace the pins if the caliper is frozen but you need to inspect the caliper soon.

njmaxseltd is correct about the frozen caliper. You may try to unbind it by twisting the piston back into position. When mine was frozen, needle-nosed pliers did not work. I used an over-sized wrench, pushed back the rubber piston seal and twisted until it broke free. I sprayed a tad of lubricant and continued twisting a bit more.

There are at least two main reasons your one caliper could stop functioning:
1. Piston is bound (twist to break free--otherwise replace caliper)
2. Grease on pins has dried out or other factor preventing free caliper movement across pins.

Think about how your calipers work (see HowStuffWorks.com for visuals) and you will more clearly be able to diagnose the problem. A caliper cannot leak internally unless it is cracked. It can leak via the bleeder screw (check for liquid being expelled when brakes are depressed), via the lines, or via the piston if your seals have worn clear through. In this case, fluid may pass to the pads and onto the rotor. The fluid comes from the lines into the housing of the caliper and sits behind the piston. When the pedal is depressed, the booster works in conjunction with the master cylinder to use hydraulic force in a steady PUMP action that fills the caliper wells and forces the piston outward. When it makes contact with the pad, the caliper is forced in the opposite direction from the rotor, sliding along the pins and bringing the other side of the caliper closer to pinch the rotor via the pads. If there is no material on your rotor (only rust) then obviously the caliper is not moving (see reasons above).

99% of the time, a spongy brake pedal is due to air in the lines. As you depress the pedal, the air bubbles collapse, yet they take up space in the lines. It's similar to pushing a brick with a balloon versus pushing a brick with another brick. You should bleed the entire system, including the master cylinder, and extract ALL of the old fluid. The two-man job is the most complete and proven system. You must ensure that ALL the air is out. I recently replaced ALL calipers, rotors, and pads, then bled the system twice over two days. I thought all the air was out the first day, but more bubbles were expelled the second time around. Be cautious with your bleeder screws to not over-torque or strip them.

Since my maintenance, I have never had a stiffer, more accurate pedal and incredible stopping force.

 

air in system